US Department of Housing and Urban Development National Association of Home Builders Office of Policy Development and Research
An Approach for the 80s Affordable Housing Demonstration
An Approach for the 80 s Affordable Housing Demonstration
Acknowledgements Many individuals contributed valuable time and expertise toward making Apshyproach 80 successful Although space does not allow a complete listing of all who contributed some individuals were so important to the projects success that without them Approach 80 would not have been possible These indishyviduals include Las Vegas builderdevelopers Dudley Smith and Ernest Beckshyer Las Vegas Mayor William Briare Las Vegas Deputy City Manager Donald Saylor and Orville Lee of HUDs Office of Policy Development and Research Also NAHBs Approach 80 Task Force co-chairman Robert Gardner Grand Junction Colorado and Larry Goldrich Virginia Beach Virginia were imporshytant individuals to the project James Cashman Riverside California was extremely helpful in obtaining approvals from the City of Las Vegas Milton Smithman NAHB Staff Vice President of Special Projects coordinated the efforts of all the participants David Jensen Denver Colorado Cy Paumier Jr Columbia Maryland and Stephen Mead Des Moines Iowa provided land plans and architectural input
In addition several building product manufacturers and trade associations were extremely helpful in providing technical expertise These included Champion International Shell Chemical Qest Plumbing Products Hoover Universal California Redwood Association Zinc Institute American Plywood Association and American Wood Preservers Institute
This report was prepared by the NAHB Research Foundation Inc for the US Department of Housing and Urban Development The statements and conclusions contained herein are those of the author E Lee Fisher Director of Industrial Engineering and do not necessarily reflect the views of the US Government in general nor HUD in particular Neither the US Government nor HUD makes any warranty expressed or implied as to the accuracy or completeness of the information contained herein
2
Contents
Tables
Acknowledgements 2
Introduction 4
Background 4
Approach 80 Concept 6
Land Development 7
Homeowners 11
The Houses 11
In-Place Cost Analysis 20
Land Development 20
Direct Construction Costs 23
Total Approach 80 Costs 23
Deviations Requested But Not Approved 25
Conclusion 31
Table 1 Approach 80 Land Plan Negotiations with the City of Las Vegas 10
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons 21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice 22
Table 4 Approach 80 Direct Construction Cost Comparison As-Built v Conventional Las Vegas Codes and Practices by Plan Number 23
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conshyventional Las Vegas Codes and Standard Practices 25
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Cateshygory and by Cost Item Within Each Category 26
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Item Within Each Category 28
Table 8 Approach 80 Estimated Potential Cost Reduction of Items Not Approved by the City of Las Vegas 30
3
Introduction
Background
Although more residential construction has occurred in America during the last few decades than in any comparable period in history the United States is facing a housing crisis of alarming proportions Costs of developed land building materials and labor plus extremely high interest rates have severely limited homeownership possibilities for all but the most affluent In addition each year brings new constraints to builders and developers in the form of governmental regulations which invariably add to the total housing cost
In addition to the added construction cost of each regulation in many areas a corresponding proliferation of governmental agencies and bureaucratic procedures have created a confusing network of approvals that are extremely time consuming and costly ultimately to the home buyer Outdated conflictshying and complicated codes and standards environmental issues and reshyquirements and energy conservation issues all add to the dilemma-and to the cost-of home ownership
Originally regulations and standards were promulgated to insure a safe and healthy environment for dwelling occupants Today many regulations have little if any relationship to health and safety However good the intention however small the cost of each regulation the sum of the controls has created a substantial cost that is added to each new home built
In addition to the additional cost of regulations the average size of new homes has increased steadily each year since World War II During this period home buyers were demanding and getting larger homes with more amenities on larger lots The situation was not dissimilar to the automobile industry that was able to create mammoth luxury cars out of small economy cars in a few short years of improvements Like homebuilding the auto industry has had to contend with increased governmental regulations rapidly rising material and labor costs as well as the consumers desire for a larger product with more gadgets
Therefore the excessive cost of producing a home has become a problem with multiple causes that will require multiple solutions to correct Against this troubled backdrop Approach 80 was conceived
For years the National Association of Home Builders (NAHB) and the NAHB Research Foundation Inc have been searching for solutions to the rising cost of housing NAHB has created special committees on affordable housing the cost of governmental regulations labor and material costs and others It has sponsored research on reasonable land development standards costshyeffective energy performance guidelines construction cost control productivshyity and management techniques Through the NAHB Research House Proshygram many innovative products and techniques have been demonstrated Indeed almost all of NAHBs standing and special committees have been charged with finding ways to produce safe and healthy homes and apartments at an affordable price
The NAHB Research Foundation a wholly owned subsidiary of NAHB has also been involved with the problem of housing affordability In addition to
4
conducting much of NAHBs research efforts over the years the Research Foundation contracted with building product manufacturers governmental agencies and individual building firms in an attempt to find solutions to housing the greatest number of Americans at the least cost Under contract to the US Department of Housing and Urban Development (HUD) the Research Foundation has developed the Optimum Value Engineered (OVE)1 construcshytion system two Energy Efficient Residences (EER) and several other cost effective housing systems products and techniques Working with the buildshying products industry the Research Foundation has developed construction systems and products that improve housing value such as the Engineered 24 inches-on-center building system
HUD has worked to develop programs to make housing affordable In addition to the OVE and EER systems HUD created a National Conference on Housing Costs which resulted in the Housing Cost Reduction Demonstration and the Building Value into Housing programs HUD also has sponsored independent research on building codes updating the Minimum Property Standards (MPS) minority housing and housing for the physically handishycapped much of which was conducted by the NAHB Research Foundation Throughout the years HUD has developed financing and subsidy programs aimed at making housing affordable to a greater number of Americans
Therefore a combination of HUD NAHB and the Research Foundation was uniquely equipped to develop a housing project that would demonstrate land development and construction methods to create lower cost homes
Entrance to Approach 80
1 Reducing Home Building Costs With OVE Design and Construction Guideline 5 Superinshytendent of Documents Washington DC Government Printing Office
5
Approach 80 Concept IA 1978 HUDs National Conference on Housing Costs called together a broad cross-section of National leaders members of the private housing sector (including NAHB and the NAHB Research Foundation) consumer interests academics and state and local officials This conference recognized the need of a multifaceted approach to reducing housing costs
At the same time Ernest Becker then president of NAHB and a Las Vegas builder became a leading industry proponent of affordable housing and asked the NAHB Standing Committee on Research to design and build two dwellings in Las Vegas in time for the 1979 NAHB ConventionExposition that would demonstrate cost-saving construction techniques without compromising health and safety of the occupants
The City of Las Vegas made special exceptions to the building code to allow the homes to be built and occupied Using conventional building materials and methods and a well-thought-out well-engineered plan builder Dudley A Smith then chairman of the Research Committee built the two Cost Buster homes The work drew heavily on past research done by the NAHB Research Foundation especially the eVE house
The Cost Buster project was conceived as a demonstration of modern economical construction free from unnecessary codes and regulations The project did not attempt to prove marketability customer acceptance or adapshytability to other locations It did clearly illustrate that a safe sturdy home can be built at reduced cost Direct construction cost savings amounted to about 25 percent of the cost of a conventionally built Las Vegas home of similar size
The Cost Buster homes made considerable impact on the residential buildshying community They were featured on a national television network newscast and articles were written about the homes in many of the nations leading newspapers and housing periodicals
The Cost Buster demonstration was extremely successful in what it was attempting to prove However valid criticisms of the project were offered
bull The design of the homes might prove unmarketable in many parts of the country
bull The homes were built on standard size lots in a conventionally developed subdivision
bull Cost of developed land in some parts of the country would be more of a factor in total sales price than direct construction cost
Cost Buster House
6
Land Development
Some builders had difficulty identifying with Cost Buster because of some construction techniques were not used in their areas For example the Cost Buster homes built on concrete slab foundationsfloors Some builders who built on basements or crawl space foundations dismissed the demonstration as being unusable back home Since the foundationfloor was only a part ofthe demonstration rejection of the total project on this basis seems to indicate that more builder education would be in order
Because of the interest in Cost Buster and the unresolved questions raised by the project a jOint task force was formed from NAHBs Standing Commitshytees on Research and Land Use
Members of this Task Force along with NAHB staff members and the Research Foundation went to HUD with the concept of an affordable house community-also to be built in Las Vegas-that would integrate efficient land planning cost effective construction and maketable design HUD agreed to help sponsor such an undertaking and offered its support in obtaining approvshyals as well as financing assistance The houses were to be built under the HUD Experimental Housing Program and to be insured under HUD Section 233 pursuant to Section 245 Graduated Mortgage Program Under Section 233 if any defects develop in the experimental aspects of these houses HUD guaranshytees their restitution and repair
Ernest Becker obtained a suitable site for the project and Dudley Smith developed the site and built the homes Both were instrumental in getting Las Vegas city officials to support the project Stephen Mead AlA of Des Moines Iowa was selected to design the housing units while the land plan work was assigned to the Land Use Committee The Research Foundation was charged with providing construction system advice and with monitoring of construction
The Approach SO Task Force met several times and agreed on a land plan and the dwelling designs The underlying theme of Approach SO was to develop a relatively high-density subdivision containing single-family deshytached homes duplexes and townhouses arranged in such a way so as to provide privacy along with a feeling of openness
The Approach SO site is a 5-acre rectangular tract located at the northwestern fringe of the urbanized area of Las Vegas The approximate dimensions of 335 feet by 6S5 feet include one-side of two major Las Vegas streets Smoke Ranch Road and Torrey Pines Drive which reduced the total area to be developed to about 42 acres The site was originally zoned as a residential planned development allowing S dwelling units per acre (RPD-S) Under existing standards the planned unit development (PUD) allows for maximum flexibility in residential design and land utilization The PUD may consist of attached or detached single-family units townhouses cluster units conshydominiums garden apartments or any combination thereof All development in an RPD was to be in acordance with the design standards adopted by the City Commission In the case of Approach SO the design standards were amended to provide maximum density and liveability at minimum cost
The RPD-S zoning on the 5 acres allowed for a density of S dwelling units per gross acre or 40 dwelling units The land plan adopted by the Approach SO task force provided 3S units-10 single-family attached units 14 duplex units and 14 units in clusters of threeplexes and fourplexes-all in a zero-lot-line configuration Prior to Approach SO the city of Las Vegas had never allowed multifamily and single-family detached units in the same subdivision
Widths of the 24 single-family lots varied from 3S to 42 feet and depths varied from SO to 90 feet which deviated from the 100-foot depth usually required The zero-lot-line location of these units allowed more efficient use of the lots Duplexes were attached at the lot line Triplexes and quadruplexes were clustered at the eastern end of the project with common areas adjacent on all sides
7
Plat Plan D II I 0 P 0
III 0 r II
Plot Plan
~
( I I I
l Q P [ 0
8
I
Typical Trench Detail
Approach 80 Under Construction
The road system within the 42 acres was designed to provide adequate movement for both vehicles and emergency equipment while minimizing high speed through traffic The goal was to provide each lot and common area with satisfactory access while limiting excessive pavement and right-ot-way to save land and development costs as well as reduce tuture maintenance costs Dead end streets were utilized where cul-de-sacs would normally be required saving land and paving costs Turnaround easements were provided
Jim Cashman a Riverside California builder and chairman ot the NAHB Land Use Committee assisted in negotiating approvals of the land plan Many of the deviations from Las Vegas standards were approved by the city while compromises were made on other requests Table 1 shows the usual Las Vegas land development requirements the deviations requested and the final approved designs
In addition longer than normal 4-inch house connection sewer service was allowed across public streets to main sewer lines located in easements The 20-inch minimum easement required tor 4-inch water lines was reduced to 18 inches More than one group ot townhouses were served by a single 2-inch domestic water meter where an individual meter is normally required for each unit Four-inch water mains were allowed in streets other than cul-de-sacs
The major perimeter streets required street lights conforming to the Las Vegas standards However the street lights installed in the interior of the
9
Table 1 Approach 80 Land Plan Negotiations with the City of Las Vegas
Item
R-1 lot size
Front yard set back
Side yard
Street right-of-way
Street paving
Dead end streets
Subdivision wall
Sidewalks
Sewer
Standard
60 x 120
25
0 10
60
41
Cul-de-sac
Concrete block
5 each side
8 mainline
Requested
40 x 80 45 X 75
15
0
10 5 garage
20 side 30 interior 34 entry
16 side 20 interior 24 entry
Tee section
Open sections and fencing
4 one side
4 amp6 main
Approved
40 X 90 45 X 80
15
0 10
5 garage
20 36 44
16 28 36
Break away barrier
Open sections and fencing
4 one side
4 amp6 main
)
---- --shy
Sewer and Water Plan UNO f I [ L 0 [ 0
== Z=--==
r----- ----- 7 bull a bull a -----------shy---~0--- 0 bull 1~
--- shy
( I I
I I
I
---+----+--
I
~ I I -
~ i I I i
o
- ~ 0
10
subdivision were the down type Ughting based on foot candle measure of lighting rather than maximum distance between lights
Homeowners
The Houses
I I
~i rf
Two Stud Corner with Metal Drywall Backup Clips
In order to provide on-going maintenance of Approach SO common areas and to ensure easement rights a homeowners association was formed complete with Articles of Incorporation and Declaration of Covenants Conditions and Restrictions
The 3S Approach SO units included 10 detached homes 7 duplexes 2 threeplexes and 2 fourplexes Units ranged in size from 704 square feet to 1 116 square feet One unit a detached split level contained 1 OOS square feet of finished living space and 392 square feet of expandable space in the lower level
Although the objective of Approach SO was to demonstrate low-cost marshyketable land development and construction techniques some of the demonshystrated systems were not necessarily the least costly way to build in Las Vegas For example Las Vegas has been traditionally a slab-on-grade town with very few crawl space and basement homes built in recent years The Approach SO committee decided however to build basement and crawl space homes to show alternatives in foundation and floor construction Conshystruction techniques and systems demonstrated included the following
Modular Design-Units were designed to a module of 2 feet out-to-out to reduce scrap waste and labor They were also designed to minimize length of walls and partitions
Value Engineering Techniques bull Trusses walls and floor joists were framed 24 inches on-center in line
with each other bull Two-stud corners were used with metal drywall backup clips bull Plywood box beam headers were used instead of solid wood headers
These headers created a cavity for insulation bull Windows 22112 inches wide were placed between studs 24 inches on
center to eliminate window headers bull In-line off-center spliced joists were used on one home This system
allowed use of smaller floor joists and reduced labor costs bull Single top plates were used on all walls bull Metal drywall backup clips eliminated studs as drywall nailers bull Single layer glue-nailed TampG plywood (Sturdi-floor) systems reduced
material and labor and contributed to a stiffer floor with fewer squeeks bull Single layer plywood siding eliminated sheathing and corner bracing bull Bulkheads (furred-down soffits) were eliminated over kitchen cabinets bull Amount of blocking and bracing was reduced bull Partition posts (channels) were eliminated
Construction Systems bull Reduced thickness and width of footing based on soil bearing tests bull A 2112 inch thick slab used in three slabs as demonstration bull Pressure treated wood foundations used in one crawl space and one
basement to demonstrate an alternative to cast-in-place concrete and conshycrete block foundations
bull Underfloor plenum heatingcooling system used in two homes System uses underfloor area as supply plenum eliminating ducts
bull Waterproof basement techniques demonstrated in basement homes bull Prefabricated DWV plumbing trees bull Polybutylene hot and cold water supply plumbing was demonstrated in
three homes
11
Triple Window Opening in Bearing Wall
single 2X4 op plate -+1_-
no headers
ead bloc
22 12 in~~~==tt==~----Hr--openings 1
2x4 24 in oc
II blocks -+1-
Open Soffit Overhang
-~ -t~1
-
22V2-lnch Wide Windows Between 24-lnch On-Center Studs Plywood Box Beam Headers
12
ps
f-shy
I shy
n
x r No Bulkhead Over Cabinets
Interior PartitionExterior Wall Connection
t
ISingle Layer Plywood Siding 34-lnch Tongue and Groove Single Layer APA Sturd-I-Floor
13
Exterior Wall 24 Inches On Center Single Top Plate
1== Single pp plate ~ I
[ jg fo (7~
=
l =
24-lnch On-Center In-Line Framing In-Line Off-Center Spliced Floor Joists
5
In-Line Off-Center Spliced Floor Joists
14
Light Gauge Steel Studs
shyPressure-Treated Wood Foundation
bull Light gauge steel studs were installed in one demonstration unit to show an alternative to wood interior partition framing
In most cases the systems demonstrated proved to be less costly than conventional techniques and systems In some cases the demonstrated system mayor may not be cost effective in some locales depending on local variations in material and labor costs
A house-by-house description of the demonstration units follows Seven of the units contained many of the systems that were being shown as techniques that might be usable in areas other than Las Vegas such as basements crawl spaces wood floor framing methods All 38 units contained value engineered framing sheathing Siding and other cost-reduction systems
Prefabricated Plastic DWV Plumbing Tree Polybutylene Water Supply Plumbing
15
- -
Plan 1-A one-story 782-square-foot twoshybedroom one-bath home featuring engineered framshying underfloor plenum heatingcooling pressure treated wood foundation steel interior partitions and polybutylene supply plumbing
-~ 7
bedoom -j 1---_--ir
-bedroom
garage
-shy
bHroom great room
garage
Plan 1 shy AllemIe ~middot~~_
An alternate version of Plan 1 was built to evaluate the value of certain architectural features in a small home Plan 1 contained an inset deck which provided a somewhat private outdoor space within the floor plan of the home The alternate version was designed without the inset and with the kitchen made 2 feet wider which added about 62 square feet of living area These changes will be evaluated as to marketability of the two units
16
Plan 2-A one-story 1040-square-foot three-bedroom two-bath home with value engineered framing and an underfloor plenum heatingcooling system
drooml Plan 3-A two-story 11 04-square-foot three-bedroom 1112 bath home
featuring waterproof basement construction and a lower-priced redwood lap concrete
siding
bedroom
dtnlng
conclII ptlO
living
patio bull
dining
garage
Plan 3
17
~-~ Plan 4-This plan was built as a split level and also as a slab-on-grade home The
split level version featured engineered framing in-line off center spliced floor joists pressure treated wood foundation and polybutylene supply plumbing It contained 1008 square feet of finished floor area with 392 square feet of expandable area in the lower level Rough-in for a second full bath was provided in the lower level
~~J
-~~
bbullbull oom edoomt --l l
F7 [- ~
-uplusmn~Ll n garage
The slab version of plan 4 contained 1008 square feet of living area two bedrooms and one bath It featured value engineered framing and polybutylene supply plumbing
18
Duplex-Each of the four floor plans was repeated in a duplex vershysion at least once within the subdivishysion The duplexes were basically the same with the obvious exception of firewalls included between units
UpperL
~hh _____ bull OL-
Threeplex
Triplex
11
Threeplex Under ConstructionshyThe threeplex buildings contained two two-story units and one one-story unit
19
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
An Approach for the 80 s Affordable Housing Demonstration
Acknowledgements Many individuals contributed valuable time and expertise toward making Apshyproach 80 successful Although space does not allow a complete listing of all who contributed some individuals were so important to the projects success that without them Approach 80 would not have been possible These indishyviduals include Las Vegas builderdevelopers Dudley Smith and Ernest Beckshyer Las Vegas Mayor William Briare Las Vegas Deputy City Manager Donald Saylor and Orville Lee of HUDs Office of Policy Development and Research Also NAHBs Approach 80 Task Force co-chairman Robert Gardner Grand Junction Colorado and Larry Goldrich Virginia Beach Virginia were imporshytant individuals to the project James Cashman Riverside California was extremely helpful in obtaining approvals from the City of Las Vegas Milton Smithman NAHB Staff Vice President of Special Projects coordinated the efforts of all the participants David Jensen Denver Colorado Cy Paumier Jr Columbia Maryland and Stephen Mead Des Moines Iowa provided land plans and architectural input
In addition several building product manufacturers and trade associations were extremely helpful in providing technical expertise These included Champion International Shell Chemical Qest Plumbing Products Hoover Universal California Redwood Association Zinc Institute American Plywood Association and American Wood Preservers Institute
This report was prepared by the NAHB Research Foundation Inc for the US Department of Housing and Urban Development The statements and conclusions contained herein are those of the author E Lee Fisher Director of Industrial Engineering and do not necessarily reflect the views of the US Government in general nor HUD in particular Neither the US Government nor HUD makes any warranty expressed or implied as to the accuracy or completeness of the information contained herein
2
Contents
Tables
Acknowledgements 2
Introduction 4
Background 4
Approach 80 Concept 6
Land Development 7
Homeowners 11
The Houses 11
In-Place Cost Analysis 20
Land Development 20
Direct Construction Costs 23
Total Approach 80 Costs 23
Deviations Requested But Not Approved 25
Conclusion 31
Table 1 Approach 80 Land Plan Negotiations with the City of Las Vegas 10
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons 21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice 22
Table 4 Approach 80 Direct Construction Cost Comparison As-Built v Conventional Las Vegas Codes and Practices by Plan Number 23
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conshyventional Las Vegas Codes and Standard Practices 25
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Cateshygory and by Cost Item Within Each Category 26
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Item Within Each Category 28
Table 8 Approach 80 Estimated Potential Cost Reduction of Items Not Approved by the City of Las Vegas 30
3
Introduction
Background
Although more residential construction has occurred in America during the last few decades than in any comparable period in history the United States is facing a housing crisis of alarming proportions Costs of developed land building materials and labor plus extremely high interest rates have severely limited homeownership possibilities for all but the most affluent In addition each year brings new constraints to builders and developers in the form of governmental regulations which invariably add to the total housing cost
In addition to the added construction cost of each regulation in many areas a corresponding proliferation of governmental agencies and bureaucratic procedures have created a confusing network of approvals that are extremely time consuming and costly ultimately to the home buyer Outdated conflictshying and complicated codes and standards environmental issues and reshyquirements and energy conservation issues all add to the dilemma-and to the cost-of home ownership
Originally regulations and standards were promulgated to insure a safe and healthy environment for dwelling occupants Today many regulations have little if any relationship to health and safety However good the intention however small the cost of each regulation the sum of the controls has created a substantial cost that is added to each new home built
In addition to the additional cost of regulations the average size of new homes has increased steadily each year since World War II During this period home buyers were demanding and getting larger homes with more amenities on larger lots The situation was not dissimilar to the automobile industry that was able to create mammoth luxury cars out of small economy cars in a few short years of improvements Like homebuilding the auto industry has had to contend with increased governmental regulations rapidly rising material and labor costs as well as the consumers desire for a larger product with more gadgets
Therefore the excessive cost of producing a home has become a problem with multiple causes that will require multiple solutions to correct Against this troubled backdrop Approach 80 was conceived
For years the National Association of Home Builders (NAHB) and the NAHB Research Foundation Inc have been searching for solutions to the rising cost of housing NAHB has created special committees on affordable housing the cost of governmental regulations labor and material costs and others It has sponsored research on reasonable land development standards costshyeffective energy performance guidelines construction cost control productivshyity and management techniques Through the NAHB Research House Proshygram many innovative products and techniques have been demonstrated Indeed almost all of NAHBs standing and special committees have been charged with finding ways to produce safe and healthy homes and apartments at an affordable price
The NAHB Research Foundation a wholly owned subsidiary of NAHB has also been involved with the problem of housing affordability In addition to
4
conducting much of NAHBs research efforts over the years the Research Foundation contracted with building product manufacturers governmental agencies and individual building firms in an attempt to find solutions to housing the greatest number of Americans at the least cost Under contract to the US Department of Housing and Urban Development (HUD) the Research Foundation has developed the Optimum Value Engineered (OVE)1 construcshytion system two Energy Efficient Residences (EER) and several other cost effective housing systems products and techniques Working with the buildshying products industry the Research Foundation has developed construction systems and products that improve housing value such as the Engineered 24 inches-on-center building system
HUD has worked to develop programs to make housing affordable In addition to the OVE and EER systems HUD created a National Conference on Housing Costs which resulted in the Housing Cost Reduction Demonstration and the Building Value into Housing programs HUD also has sponsored independent research on building codes updating the Minimum Property Standards (MPS) minority housing and housing for the physically handishycapped much of which was conducted by the NAHB Research Foundation Throughout the years HUD has developed financing and subsidy programs aimed at making housing affordable to a greater number of Americans
Therefore a combination of HUD NAHB and the Research Foundation was uniquely equipped to develop a housing project that would demonstrate land development and construction methods to create lower cost homes
Entrance to Approach 80
1 Reducing Home Building Costs With OVE Design and Construction Guideline 5 Superinshytendent of Documents Washington DC Government Printing Office
5
Approach 80 Concept IA 1978 HUDs National Conference on Housing Costs called together a broad cross-section of National leaders members of the private housing sector (including NAHB and the NAHB Research Foundation) consumer interests academics and state and local officials This conference recognized the need of a multifaceted approach to reducing housing costs
At the same time Ernest Becker then president of NAHB and a Las Vegas builder became a leading industry proponent of affordable housing and asked the NAHB Standing Committee on Research to design and build two dwellings in Las Vegas in time for the 1979 NAHB ConventionExposition that would demonstrate cost-saving construction techniques without compromising health and safety of the occupants
The City of Las Vegas made special exceptions to the building code to allow the homes to be built and occupied Using conventional building materials and methods and a well-thought-out well-engineered plan builder Dudley A Smith then chairman of the Research Committee built the two Cost Buster homes The work drew heavily on past research done by the NAHB Research Foundation especially the eVE house
The Cost Buster project was conceived as a demonstration of modern economical construction free from unnecessary codes and regulations The project did not attempt to prove marketability customer acceptance or adapshytability to other locations It did clearly illustrate that a safe sturdy home can be built at reduced cost Direct construction cost savings amounted to about 25 percent of the cost of a conventionally built Las Vegas home of similar size
The Cost Buster homes made considerable impact on the residential buildshying community They were featured on a national television network newscast and articles were written about the homes in many of the nations leading newspapers and housing periodicals
The Cost Buster demonstration was extremely successful in what it was attempting to prove However valid criticisms of the project were offered
bull The design of the homes might prove unmarketable in many parts of the country
bull The homes were built on standard size lots in a conventionally developed subdivision
bull Cost of developed land in some parts of the country would be more of a factor in total sales price than direct construction cost
Cost Buster House
6
Land Development
Some builders had difficulty identifying with Cost Buster because of some construction techniques were not used in their areas For example the Cost Buster homes built on concrete slab foundationsfloors Some builders who built on basements or crawl space foundations dismissed the demonstration as being unusable back home Since the foundationfloor was only a part ofthe demonstration rejection of the total project on this basis seems to indicate that more builder education would be in order
Because of the interest in Cost Buster and the unresolved questions raised by the project a jOint task force was formed from NAHBs Standing Commitshytees on Research and Land Use
Members of this Task Force along with NAHB staff members and the Research Foundation went to HUD with the concept of an affordable house community-also to be built in Las Vegas-that would integrate efficient land planning cost effective construction and maketable design HUD agreed to help sponsor such an undertaking and offered its support in obtaining approvshyals as well as financing assistance The houses were to be built under the HUD Experimental Housing Program and to be insured under HUD Section 233 pursuant to Section 245 Graduated Mortgage Program Under Section 233 if any defects develop in the experimental aspects of these houses HUD guaranshytees their restitution and repair
Ernest Becker obtained a suitable site for the project and Dudley Smith developed the site and built the homes Both were instrumental in getting Las Vegas city officials to support the project Stephen Mead AlA of Des Moines Iowa was selected to design the housing units while the land plan work was assigned to the Land Use Committee The Research Foundation was charged with providing construction system advice and with monitoring of construction
The Approach SO Task Force met several times and agreed on a land plan and the dwelling designs The underlying theme of Approach SO was to develop a relatively high-density subdivision containing single-family deshytached homes duplexes and townhouses arranged in such a way so as to provide privacy along with a feeling of openness
The Approach SO site is a 5-acre rectangular tract located at the northwestern fringe of the urbanized area of Las Vegas The approximate dimensions of 335 feet by 6S5 feet include one-side of two major Las Vegas streets Smoke Ranch Road and Torrey Pines Drive which reduced the total area to be developed to about 42 acres The site was originally zoned as a residential planned development allowing S dwelling units per acre (RPD-S) Under existing standards the planned unit development (PUD) allows for maximum flexibility in residential design and land utilization The PUD may consist of attached or detached single-family units townhouses cluster units conshydominiums garden apartments or any combination thereof All development in an RPD was to be in acordance with the design standards adopted by the City Commission In the case of Approach SO the design standards were amended to provide maximum density and liveability at minimum cost
The RPD-S zoning on the 5 acres allowed for a density of S dwelling units per gross acre or 40 dwelling units The land plan adopted by the Approach SO task force provided 3S units-10 single-family attached units 14 duplex units and 14 units in clusters of threeplexes and fourplexes-all in a zero-lot-line configuration Prior to Approach SO the city of Las Vegas had never allowed multifamily and single-family detached units in the same subdivision
Widths of the 24 single-family lots varied from 3S to 42 feet and depths varied from SO to 90 feet which deviated from the 100-foot depth usually required The zero-lot-line location of these units allowed more efficient use of the lots Duplexes were attached at the lot line Triplexes and quadruplexes were clustered at the eastern end of the project with common areas adjacent on all sides
7
Plat Plan D II I 0 P 0
III 0 r II
Plot Plan
~
( I I I
l Q P [ 0
8
I
Typical Trench Detail
Approach 80 Under Construction
The road system within the 42 acres was designed to provide adequate movement for both vehicles and emergency equipment while minimizing high speed through traffic The goal was to provide each lot and common area with satisfactory access while limiting excessive pavement and right-ot-way to save land and development costs as well as reduce tuture maintenance costs Dead end streets were utilized where cul-de-sacs would normally be required saving land and paving costs Turnaround easements were provided
Jim Cashman a Riverside California builder and chairman ot the NAHB Land Use Committee assisted in negotiating approvals of the land plan Many of the deviations from Las Vegas standards were approved by the city while compromises were made on other requests Table 1 shows the usual Las Vegas land development requirements the deviations requested and the final approved designs
In addition longer than normal 4-inch house connection sewer service was allowed across public streets to main sewer lines located in easements The 20-inch minimum easement required tor 4-inch water lines was reduced to 18 inches More than one group ot townhouses were served by a single 2-inch domestic water meter where an individual meter is normally required for each unit Four-inch water mains were allowed in streets other than cul-de-sacs
The major perimeter streets required street lights conforming to the Las Vegas standards However the street lights installed in the interior of the
9
Table 1 Approach 80 Land Plan Negotiations with the City of Las Vegas
Item
R-1 lot size
Front yard set back
Side yard
Street right-of-way
Street paving
Dead end streets
Subdivision wall
Sidewalks
Sewer
Standard
60 x 120
25
0 10
60
41
Cul-de-sac
Concrete block
5 each side
8 mainline
Requested
40 x 80 45 X 75
15
0
10 5 garage
20 side 30 interior 34 entry
16 side 20 interior 24 entry
Tee section
Open sections and fencing
4 one side
4 amp6 main
Approved
40 X 90 45 X 80
15
0 10
5 garage
20 36 44
16 28 36
Break away barrier
Open sections and fencing
4 one side
4 amp6 main
)
---- --shy
Sewer and Water Plan UNO f I [ L 0 [ 0
== Z=--==
r----- ----- 7 bull a bull a -----------shy---~0--- 0 bull 1~
--- shy
( I I
I I
I
---+----+--
I
~ I I -
~ i I I i
o
- ~ 0
10
subdivision were the down type Ughting based on foot candle measure of lighting rather than maximum distance between lights
Homeowners
The Houses
I I
~i rf
Two Stud Corner with Metal Drywall Backup Clips
In order to provide on-going maintenance of Approach SO common areas and to ensure easement rights a homeowners association was formed complete with Articles of Incorporation and Declaration of Covenants Conditions and Restrictions
The 3S Approach SO units included 10 detached homes 7 duplexes 2 threeplexes and 2 fourplexes Units ranged in size from 704 square feet to 1 116 square feet One unit a detached split level contained 1 OOS square feet of finished living space and 392 square feet of expandable space in the lower level
Although the objective of Approach SO was to demonstrate low-cost marshyketable land development and construction techniques some of the demonshystrated systems were not necessarily the least costly way to build in Las Vegas For example Las Vegas has been traditionally a slab-on-grade town with very few crawl space and basement homes built in recent years The Approach SO committee decided however to build basement and crawl space homes to show alternatives in foundation and floor construction Conshystruction techniques and systems demonstrated included the following
Modular Design-Units were designed to a module of 2 feet out-to-out to reduce scrap waste and labor They were also designed to minimize length of walls and partitions
Value Engineering Techniques bull Trusses walls and floor joists were framed 24 inches on-center in line
with each other bull Two-stud corners were used with metal drywall backup clips bull Plywood box beam headers were used instead of solid wood headers
These headers created a cavity for insulation bull Windows 22112 inches wide were placed between studs 24 inches on
center to eliminate window headers bull In-line off-center spliced joists were used on one home This system
allowed use of smaller floor joists and reduced labor costs bull Single top plates were used on all walls bull Metal drywall backup clips eliminated studs as drywall nailers bull Single layer glue-nailed TampG plywood (Sturdi-floor) systems reduced
material and labor and contributed to a stiffer floor with fewer squeeks bull Single layer plywood siding eliminated sheathing and corner bracing bull Bulkheads (furred-down soffits) were eliminated over kitchen cabinets bull Amount of blocking and bracing was reduced bull Partition posts (channels) were eliminated
Construction Systems bull Reduced thickness and width of footing based on soil bearing tests bull A 2112 inch thick slab used in three slabs as demonstration bull Pressure treated wood foundations used in one crawl space and one
basement to demonstrate an alternative to cast-in-place concrete and conshycrete block foundations
bull Underfloor plenum heatingcooling system used in two homes System uses underfloor area as supply plenum eliminating ducts
bull Waterproof basement techniques demonstrated in basement homes bull Prefabricated DWV plumbing trees bull Polybutylene hot and cold water supply plumbing was demonstrated in
three homes
11
Triple Window Opening in Bearing Wall
single 2X4 op plate -+1_-
no headers
ead bloc
22 12 in~~~==tt==~----Hr--openings 1
2x4 24 in oc
II blocks -+1-
Open Soffit Overhang
-~ -t~1
-
22V2-lnch Wide Windows Between 24-lnch On-Center Studs Plywood Box Beam Headers
12
ps
f-shy
I shy
n
x r No Bulkhead Over Cabinets
Interior PartitionExterior Wall Connection
t
ISingle Layer Plywood Siding 34-lnch Tongue and Groove Single Layer APA Sturd-I-Floor
13
Exterior Wall 24 Inches On Center Single Top Plate
1== Single pp plate ~ I
[ jg fo (7~
=
l =
24-lnch On-Center In-Line Framing In-Line Off-Center Spliced Floor Joists
5
In-Line Off-Center Spliced Floor Joists
14
Light Gauge Steel Studs
shyPressure-Treated Wood Foundation
bull Light gauge steel studs were installed in one demonstration unit to show an alternative to wood interior partition framing
In most cases the systems demonstrated proved to be less costly than conventional techniques and systems In some cases the demonstrated system mayor may not be cost effective in some locales depending on local variations in material and labor costs
A house-by-house description of the demonstration units follows Seven of the units contained many of the systems that were being shown as techniques that might be usable in areas other than Las Vegas such as basements crawl spaces wood floor framing methods All 38 units contained value engineered framing sheathing Siding and other cost-reduction systems
Prefabricated Plastic DWV Plumbing Tree Polybutylene Water Supply Plumbing
15
- -
Plan 1-A one-story 782-square-foot twoshybedroom one-bath home featuring engineered framshying underfloor plenum heatingcooling pressure treated wood foundation steel interior partitions and polybutylene supply plumbing
-~ 7
bedoom -j 1---_--ir
-bedroom
garage
-shy
bHroom great room
garage
Plan 1 shy AllemIe ~middot~~_
An alternate version of Plan 1 was built to evaluate the value of certain architectural features in a small home Plan 1 contained an inset deck which provided a somewhat private outdoor space within the floor plan of the home The alternate version was designed without the inset and with the kitchen made 2 feet wider which added about 62 square feet of living area These changes will be evaluated as to marketability of the two units
16
Plan 2-A one-story 1040-square-foot three-bedroom two-bath home with value engineered framing and an underfloor plenum heatingcooling system
drooml Plan 3-A two-story 11 04-square-foot three-bedroom 1112 bath home
featuring waterproof basement construction and a lower-priced redwood lap concrete
siding
bedroom
dtnlng
conclII ptlO
living
patio bull
dining
garage
Plan 3
17
~-~ Plan 4-This plan was built as a split level and also as a slab-on-grade home The
split level version featured engineered framing in-line off center spliced floor joists pressure treated wood foundation and polybutylene supply plumbing It contained 1008 square feet of finished floor area with 392 square feet of expandable area in the lower level Rough-in for a second full bath was provided in the lower level
~~J
-~~
bbullbull oom edoomt --l l
F7 [- ~
-uplusmn~Ll n garage
The slab version of plan 4 contained 1008 square feet of living area two bedrooms and one bath It featured value engineered framing and polybutylene supply plumbing
18
Duplex-Each of the four floor plans was repeated in a duplex vershysion at least once within the subdivishysion The duplexes were basically the same with the obvious exception of firewalls included between units
UpperL
~hh _____ bull OL-
Threeplex
Triplex
11
Threeplex Under ConstructionshyThe threeplex buildings contained two two-story units and one one-story unit
19
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Acknowledgements Many individuals contributed valuable time and expertise toward making Apshyproach 80 successful Although space does not allow a complete listing of all who contributed some individuals were so important to the projects success that without them Approach 80 would not have been possible These indishyviduals include Las Vegas builderdevelopers Dudley Smith and Ernest Beckshyer Las Vegas Mayor William Briare Las Vegas Deputy City Manager Donald Saylor and Orville Lee of HUDs Office of Policy Development and Research Also NAHBs Approach 80 Task Force co-chairman Robert Gardner Grand Junction Colorado and Larry Goldrich Virginia Beach Virginia were imporshytant individuals to the project James Cashman Riverside California was extremely helpful in obtaining approvals from the City of Las Vegas Milton Smithman NAHB Staff Vice President of Special Projects coordinated the efforts of all the participants David Jensen Denver Colorado Cy Paumier Jr Columbia Maryland and Stephen Mead Des Moines Iowa provided land plans and architectural input
In addition several building product manufacturers and trade associations were extremely helpful in providing technical expertise These included Champion International Shell Chemical Qest Plumbing Products Hoover Universal California Redwood Association Zinc Institute American Plywood Association and American Wood Preservers Institute
This report was prepared by the NAHB Research Foundation Inc for the US Department of Housing and Urban Development The statements and conclusions contained herein are those of the author E Lee Fisher Director of Industrial Engineering and do not necessarily reflect the views of the US Government in general nor HUD in particular Neither the US Government nor HUD makes any warranty expressed or implied as to the accuracy or completeness of the information contained herein
2
Contents
Tables
Acknowledgements 2
Introduction 4
Background 4
Approach 80 Concept 6
Land Development 7
Homeowners 11
The Houses 11
In-Place Cost Analysis 20
Land Development 20
Direct Construction Costs 23
Total Approach 80 Costs 23
Deviations Requested But Not Approved 25
Conclusion 31
Table 1 Approach 80 Land Plan Negotiations with the City of Las Vegas 10
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons 21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice 22
Table 4 Approach 80 Direct Construction Cost Comparison As-Built v Conventional Las Vegas Codes and Practices by Plan Number 23
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conshyventional Las Vegas Codes and Standard Practices 25
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Cateshygory and by Cost Item Within Each Category 26
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Item Within Each Category 28
Table 8 Approach 80 Estimated Potential Cost Reduction of Items Not Approved by the City of Las Vegas 30
3
Introduction
Background
Although more residential construction has occurred in America during the last few decades than in any comparable period in history the United States is facing a housing crisis of alarming proportions Costs of developed land building materials and labor plus extremely high interest rates have severely limited homeownership possibilities for all but the most affluent In addition each year brings new constraints to builders and developers in the form of governmental regulations which invariably add to the total housing cost
In addition to the added construction cost of each regulation in many areas a corresponding proliferation of governmental agencies and bureaucratic procedures have created a confusing network of approvals that are extremely time consuming and costly ultimately to the home buyer Outdated conflictshying and complicated codes and standards environmental issues and reshyquirements and energy conservation issues all add to the dilemma-and to the cost-of home ownership
Originally regulations and standards were promulgated to insure a safe and healthy environment for dwelling occupants Today many regulations have little if any relationship to health and safety However good the intention however small the cost of each regulation the sum of the controls has created a substantial cost that is added to each new home built
In addition to the additional cost of regulations the average size of new homes has increased steadily each year since World War II During this period home buyers were demanding and getting larger homes with more amenities on larger lots The situation was not dissimilar to the automobile industry that was able to create mammoth luxury cars out of small economy cars in a few short years of improvements Like homebuilding the auto industry has had to contend with increased governmental regulations rapidly rising material and labor costs as well as the consumers desire for a larger product with more gadgets
Therefore the excessive cost of producing a home has become a problem with multiple causes that will require multiple solutions to correct Against this troubled backdrop Approach 80 was conceived
For years the National Association of Home Builders (NAHB) and the NAHB Research Foundation Inc have been searching for solutions to the rising cost of housing NAHB has created special committees on affordable housing the cost of governmental regulations labor and material costs and others It has sponsored research on reasonable land development standards costshyeffective energy performance guidelines construction cost control productivshyity and management techniques Through the NAHB Research House Proshygram many innovative products and techniques have been demonstrated Indeed almost all of NAHBs standing and special committees have been charged with finding ways to produce safe and healthy homes and apartments at an affordable price
The NAHB Research Foundation a wholly owned subsidiary of NAHB has also been involved with the problem of housing affordability In addition to
4
conducting much of NAHBs research efforts over the years the Research Foundation contracted with building product manufacturers governmental agencies and individual building firms in an attempt to find solutions to housing the greatest number of Americans at the least cost Under contract to the US Department of Housing and Urban Development (HUD) the Research Foundation has developed the Optimum Value Engineered (OVE)1 construcshytion system two Energy Efficient Residences (EER) and several other cost effective housing systems products and techniques Working with the buildshying products industry the Research Foundation has developed construction systems and products that improve housing value such as the Engineered 24 inches-on-center building system
HUD has worked to develop programs to make housing affordable In addition to the OVE and EER systems HUD created a National Conference on Housing Costs which resulted in the Housing Cost Reduction Demonstration and the Building Value into Housing programs HUD also has sponsored independent research on building codes updating the Minimum Property Standards (MPS) minority housing and housing for the physically handishycapped much of which was conducted by the NAHB Research Foundation Throughout the years HUD has developed financing and subsidy programs aimed at making housing affordable to a greater number of Americans
Therefore a combination of HUD NAHB and the Research Foundation was uniquely equipped to develop a housing project that would demonstrate land development and construction methods to create lower cost homes
Entrance to Approach 80
1 Reducing Home Building Costs With OVE Design and Construction Guideline 5 Superinshytendent of Documents Washington DC Government Printing Office
5
Approach 80 Concept IA 1978 HUDs National Conference on Housing Costs called together a broad cross-section of National leaders members of the private housing sector (including NAHB and the NAHB Research Foundation) consumer interests academics and state and local officials This conference recognized the need of a multifaceted approach to reducing housing costs
At the same time Ernest Becker then president of NAHB and a Las Vegas builder became a leading industry proponent of affordable housing and asked the NAHB Standing Committee on Research to design and build two dwellings in Las Vegas in time for the 1979 NAHB ConventionExposition that would demonstrate cost-saving construction techniques without compromising health and safety of the occupants
The City of Las Vegas made special exceptions to the building code to allow the homes to be built and occupied Using conventional building materials and methods and a well-thought-out well-engineered plan builder Dudley A Smith then chairman of the Research Committee built the two Cost Buster homes The work drew heavily on past research done by the NAHB Research Foundation especially the eVE house
The Cost Buster project was conceived as a demonstration of modern economical construction free from unnecessary codes and regulations The project did not attempt to prove marketability customer acceptance or adapshytability to other locations It did clearly illustrate that a safe sturdy home can be built at reduced cost Direct construction cost savings amounted to about 25 percent of the cost of a conventionally built Las Vegas home of similar size
The Cost Buster homes made considerable impact on the residential buildshying community They were featured on a national television network newscast and articles were written about the homes in many of the nations leading newspapers and housing periodicals
The Cost Buster demonstration was extremely successful in what it was attempting to prove However valid criticisms of the project were offered
bull The design of the homes might prove unmarketable in many parts of the country
bull The homes were built on standard size lots in a conventionally developed subdivision
bull Cost of developed land in some parts of the country would be more of a factor in total sales price than direct construction cost
Cost Buster House
6
Land Development
Some builders had difficulty identifying with Cost Buster because of some construction techniques were not used in their areas For example the Cost Buster homes built on concrete slab foundationsfloors Some builders who built on basements or crawl space foundations dismissed the demonstration as being unusable back home Since the foundationfloor was only a part ofthe demonstration rejection of the total project on this basis seems to indicate that more builder education would be in order
Because of the interest in Cost Buster and the unresolved questions raised by the project a jOint task force was formed from NAHBs Standing Commitshytees on Research and Land Use
Members of this Task Force along with NAHB staff members and the Research Foundation went to HUD with the concept of an affordable house community-also to be built in Las Vegas-that would integrate efficient land planning cost effective construction and maketable design HUD agreed to help sponsor such an undertaking and offered its support in obtaining approvshyals as well as financing assistance The houses were to be built under the HUD Experimental Housing Program and to be insured under HUD Section 233 pursuant to Section 245 Graduated Mortgage Program Under Section 233 if any defects develop in the experimental aspects of these houses HUD guaranshytees their restitution and repair
Ernest Becker obtained a suitable site for the project and Dudley Smith developed the site and built the homes Both were instrumental in getting Las Vegas city officials to support the project Stephen Mead AlA of Des Moines Iowa was selected to design the housing units while the land plan work was assigned to the Land Use Committee The Research Foundation was charged with providing construction system advice and with monitoring of construction
The Approach SO Task Force met several times and agreed on a land plan and the dwelling designs The underlying theme of Approach SO was to develop a relatively high-density subdivision containing single-family deshytached homes duplexes and townhouses arranged in such a way so as to provide privacy along with a feeling of openness
The Approach SO site is a 5-acre rectangular tract located at the northwestern fringe of the urbanized area of Las Vegas The approximate dimensions of 335 feet by 6S5 feet include one-side of two major Las Vegas streets Smoke Ranch Road and Torrey Pines Drive which reduced the total area to be developed to about 42 acres The site was originally zoned as a residential planned development allowing S dwelling units per acre (RPD-S) Under existing standards the planned unit development (PUD) allows for maximum flexibility in residential design and land utilization The PUD may consist of attached or detached single-family units townhouses cluster units conshydominiums garden apartments or any combination thereof All development in an RPD was to be in acordance with the design standards adopted by the City Commission In the case of Approach SO the design standards were amended to provide maximum density and liveability at minimum cost
The RPD-S zoning on the 5 acres allowed for a density of S dwelling units per gross acre or 40 dwelling units The land plan adopted by the Approach SO task force provided 3S units-10 single-family attached units 14 duplex units and 14 units in clusters of threeplexes and fourplexes-all in a zero-lot-line configuration Prior to Approach SO the city of Las Vegas had never allowed multifamily and single-family detached units in the same subdivision
Widths of the 24 single-family lots varied from 3S to 42 feet and depths varied from SO to 90 feet which deviated from the 100-foot depth usually required The zero-lot-line location of these units allowed more efficient use of the lots Duplexes were attached at the lot line Triplexes and quadruplexes were clustered at the eastern end of the project with common areas adjacent on all sides
7
Plat Plan D II I 0 P 0
III 0 r II
Plot Plan
~
( I I I
l Q P [ 0
8
I
Typical Trench Detail
Approach 80 Under Construction
The road system within the 42 acres was designed to provide adequate movement for both vehicles and emergency equipment while minimizing high speed through traffic The goal was to provide each lot and common area with satisfactory access while limiting excessive pavement and right-ot-way to save land and development costs as well as reduce tuture maintenance costs Dead end streets were utilized where cul-de-sacs would normally be required saving land and paving costs Turnaround easements were provided
Jim Cashman a Riverside California builder and chairman ot the NAHB Land Use Committee assisted in negotiating approvals of the land plan Many of the deviations from Las Vegas standards were approved by the city while compromises were made on other requests Table 1 shows the usual Las Vegas land development requirements the deviations requested and the final approved designs
In addition longer than normal 4-inch house connection sewer service was allowed across public streets to main sewer lines located in easements The 20-inch minimum easement required tor 4-inch water lines was reduced to 18 inches More than one group ot townhouses were served by a single 2-inch domestic water meter where an individual meter is normally required for each unit Four-inch water mains were allowed in streets other than cul-de-sacs
The major perimeter streets required street lights conforming to the Las Vegas standards However the street lights installed in the interior of the
9
Table 1 Approach 80 Land Plan Negotiations with the City of Las Vegas
Item
R-1 lot size
Front yard set back
Side yard
Street right-of-way
Street paving
Dead end streets
Subdivision wall
Sidewalks
Sewer
Standard
60 x 120
25
0 10
60
41
Cul-de-sac
Concrete block
5 each side
8 mainline
Requested
40 x 80 45 X 75
15
0
10 5 garage
20 side 30 interior 34 entry
16 side 20 interior 24 entry
Tee section
Open sections and fencing
4 one side
4 amp6 main
Approved
40 X 90 45 X 80
15
0 10
5 garage
20 36 44
16 28 36
Break away barrier
Open sections and fencing
4 one side
4 amp6 main
)
---- --shy
Sewer and Water Plan UNO f I [ L 0 [ 0
== Z=--==
r----- ----- 7 bull a bull a -----------shy---~0--- 0 bull 1~
--- shy
( I I
I I
I
---+----+--
I
~ I I -
~ i I I i
o
- ~ 0
10
subdivision were the down type Ughting based on foot candle measure of lighting rather than maximum distance between lights
Homeowners
The Houses
I I
~i rf
Two Stud Corner with Metal Drywall Backup Clips
In order to provide on-going maintenance of Approach SO common areas and to ensure easement rights a homeowners association was formed complete with Articles of Incorporation and Declaration of Covenants Conditions and Restrictions
The 3S Approach SO units included 10 detached homes 7 duplexes 2 threeplexes and 2 fourplexes Units ranged in size from 704 square feet to 1 116 square feet One unit a detached split level contained 1 OOS square feet of finished living space and 392 square feet of expandable space in the lower level
Although the objective of Approach SO was to demonstrate low-cost marshyketable land development and construction techniques some of the demonshystrated systems were not necessarily the least costly way to build in Las Vegas For example Las Vegas has been traditionally a slab-on-grade town with very few crawl space and basement homes built in recent years The Approach SO committee decided however to build basement and crawl space homes to show alternatives in foundation and floor construction Conshystruction techniques and systems demonstrated included the following
Modular Design-Units were designed to a module of 2 feet out-to-out to reduce scrap waste and labor They were also designed to minimize length of walls and partitions
Value Engineering Techniques bull Trusses walls and floor joists were framed 24 inches on-center in line
with each other bull Two-stud corners were used with metal drywall backup clips bull Plywood box beam headers were used instead of solid wood headers
These headers created a cavity for insulation bull Windows 22112 inches wide were placed between studs 24 inches on
center to eliminate window headers bull In-line off-center spliced joists were used on one home This system
allowed use of smaller floor joists and reduced labor costs bull Single top plates were used on all walls bull Metal drywall backup clips eliminated studs as drywall nailers bull Single layer glue-nailed TampG plywood (Sturdi-floor) systems reduced
material and labor and contributed to a stiffer floor with fewer squeeks bull Single layer plywood siding eliminated sheathing and corner bracing bull Bulkheads (furred-down soffits) were eliminated over kitchen cabinets bull Amount of blocking and bracing was reduced bull Partition posts (channels) were eliminated
Construction Systems bull Reduced thickness and width of footing based on soil bearing tests bull A 2112 inch thick slab used in three slabs as demonstration bull Pressure treated wood foundations used in one crawl space and one
basement to demonstrate an alternative to cast-in-place concrete and conshycrete block foundations
bull Underfloor plenum heatingcooling system used in two homes System uses underfloor area as supply plenum eliminating ducts
bull Waterproof basement techniques demonstrated in basement homes bull Prefabricated DWV plumbing trees bull Polybutylene hot and cold water supply plumbing was demonstrated in
three homes
11
Triple Window Opening in Bearing Wall
single 2X4 op plate -+1_-
no headers
ead bloc
22 12 in~~~==tt==~----Hr--openings 1
2x4 24 in oc
II blocks -+1-
Open Soffit Overhang
-~ -t~1
-
22V2-lnch Wide Windows Between 24-lnch On-Center Studs Plywood Box Beam Headers
12
ps
f-shy
I shy
n
x r No Bulkhead Over Cabinets
Interior PartitionExterior Wall Connection
t
ISingle Layer Plywood Siding 34-lnch Tongue and Groove Single Layer APA Sturd-I-Floor
13
Exterior Wall 24 Inches On Center Single Top Plate
1== Single pp plate ~ I
[ jg fo (7~
=
l =
24-lnch On-Center In-Line Framing In-Line Off-Center Spliced Floor Joists
5
In-Line Off-Center Spliced Floor Joists
14
Light Gauge Steel Studs
shyPressure-Treated Wood Foundation
bull Light gauge steel studs were installed in one demonstration unit to show an alternative to wood interior partition framing
In most cases the systems demonstrated proved to be less costly than conventional techniques and systems In some cases the demonstrated system mayor may not be cost effective in some locales depending on local variations in material and labor costs
A house-by-house description of the demonstration units follows Seven of the units contained many of the systems that were being shown as techniques that might be usable in areas other than Las Vegas such as basements crawl spaces wood floor framing methods All 38 units contained value engineered framing sheathing Siding and other cost-reduction systems
Prefabricated Plastic DWV Plumbing Tree Polybutylene Water Supply Plumbing
15
- -
Plan 1-A one-story 782-square-foot twoshybedroom one-bath home featuring engineered framshying underfloor plenum heatingcooling pressure treated wood foundation steel interior partitions and polybutylene supply plumbing
-~ 7
bedoom -j 1---_--ir
-bedroom
garage
-shy
bHroom great room
garage
Plan 1 shy AllemIe ~middot~~_
An alternate version of Plan 1 was built to evaluate the value of certain architectural features in a small home Plan 1 contained an inset deck which provided a somewhat private outdoor space within the floor plan of the home The alternate version was designed without the inset and with the kitchen made 2 feet wider which added about 62 square feet of living area These changes will be evaluated as to marketability of the two units
16
Plan 2-A one-story 1040-square-foot three-bedroom two-bath home with value engineered framing and an underfloor plenum heatingcooling system
drooml Plan 3-A two-story 11 04-square-foot three-bedroom 1112 bath home
featuring waterproof basement construction and a lower-priced redwood lap concrete
siding
bedroom
dtnlng
conclII ptlO
living
patio bull
dining
garage
Plan 3
17
~-~ Plan 4-This plan was built as a split level and also as a slab-on-grade home The
split level version featured engineered framing in-line off center spliced floor joists pressure treated wood foundation and polybutylene supply plumbing It contained 1008 square feet of finished floor area with 392 square feet of expandable area in the lower level Rough-in for a second full bath was provided in the lower level
~~J
-~~
bbullbull oom edoomt --l l
F7 [- ~
-uplusmn~Ll n garage
The slab version of plan 4 contained 1008 square feet of living area two bedrooms and one bath It featured value engineered framing and polybutylene supply plumbing
18
Duplex-Each of the four floor plans was repeated in a duplex vershysion at least once within the subdivishysion The duplexes were basically the same with the obvious exception of firewalls included between units
UpperL
~hh _____ bull OL-
Threeplex
Triplex
11
Threeplex Under ConstructionshyThe threeplex buildings contained two two-story units and one one-story unit
19
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Contents
Tables
Acknowledgements 2
Introduction 4
Background 4
Approach 80 Concept 6
Land Development 7
Homeowners 11
The Houses 11
In-Place Cost Analysis 20
Land Development 20
Direct Construction Costs 23
Total Approach 80 Costs 23
Deviations Requested But Not Approved 25
Conclusion 31
Table 1 Approach 80 Land Plan Negotiations with the City of Las Vegas 10
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons 21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice 22
Table 4 Approach 80 Direct Construction Cost Comparison As-Built v Conventional Las Vegas Codes and Practices by Plan Number 23
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conshyventional Las Vegas Codes and Standard Practices 25
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Cateshygory and by Cost Item Within Each Category 26
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Item Within Each Category 28
Table 8 Approach 80 Estimated Potential Cost Reduction of Items Not Approved by the City of Las Vegas 30
3
Introduction
Background
Although more residential construction has occurred in America during the last few decades than in any comparable period in history the United States is facing a housing crisis of alarming proportions Costs of developed land building materials and labor plus extremely high interest rates have severely limited homeownership possibilities for all but the most affluent In addition each year brings new constraints to builders and developers in the form of governmental regulations which invariably add to the total housing cost
In addition to the added construction cost of each regulation in many areas a corresponding proliferation of governmental agencies and bureaucratic procedures have created a confusing network of approvals that are extremely time consuming and costly ultimately to the home buyer Outdated conflictshying and complicated codes and standards environmental issues and reshyquirements and energy conservation issues all add to the dilemma-and to the cost-of home ownership
Originally regulations and standards were promulgated to insure a safe and healthy environment for dwelling occupants Today many regulations have little if any relationship to health and safety However good the intention however small the cost of each regulation the sum of the controls has created a substantial cost that is added to each new home built
In addition to the additional cost of regulations the average size of new homes has increased steadily each year since World War II During this period home buyers were demanding and getting larger homes with more amenities on larger lots The situation was not dissimilar to the automobile industry that was able to create mammoth luxury cars out of small economy cars in a few short years of improvements Like homebuilding the auto industry has had to contend with increased governmental regulations rapidly rising material and labor costs as well as the consumers desire for a larger product with more gadgets
Therefore the excessive cost of producing a home has become a problem with multiple causes that will require multiple solutions to correct Against this troubled backdrop Approach 80 was conceived
For years the National Association of Home Builders (NAHB) and the NAHB Research Foundation Inc have been searching for solutions to the rising cost of housing NAHB has created special committees on affordable housing the cost of governmental regulations labor and material costs and others It has sponsored research on reasonable land development standards costshyeffective energy performance guidelines construction cost control productivshyity and management techniques Through the NAHB Research House Proshygram many innovative products and techniques have been demonstrated Indeed almost all of NAHBs standing and special committees have been charged with finding ways to produce safe and healthy homes and apartments at an affordable price
The NAHB Research Foundation a wholly owned subsidiary of NAHB has also been involved with the problem of housing affordability In addition to
4
conducting much of NAHBs research efforts over the years the Research Foundation contracted with building product manufacturers governmental agencies and individual building firms in an attempt to find solutions to housing the greatest number of Americans at the least cost Under contract to the US Department of Housing and Urban Development (HUD) the Research Foundation has developed the Optimum Value Engineered (OVE)1 construcshytion system two Energy Efficient Residences (EER) and several other cost effective housing systems products and techniques Working with the buildshying products industry the Research Foundation has developed construction systems and products that improve housing value such as the Engineered 24 inches-on-center building system
HUD has worked to develop programs to make housing affordable In addition to the OVE and EER systems HUD created a National Conference on Housing Costs which resulted in the Housing Cost Reduction Demonstration and the Building Value into Housing programs HUD also has sponsored independent research on building codes updating the Minimum Property Standards (MPS) minority housing and housing for the physically handishycapped much of which was conducted by the NAHB Research Foundation Throughout the years HUD has developed financing and subsidy programs aimed at making housing affordable to a greater number of Americans
Therefore a combination of HUD NAHB and the Research Foundation was uniquely equipped to develop a housing project that would demonstrate land development and construction methods to create lower cost homes
Entrance to Approach 80
1 Reducing Home Building Costs With OVE Design and Construction Guideline 5 Superinshytendent of Documents Washington DC Government Printing Office
5
Approach 80 Concept IA 1978 HUDs National Conference on Housing Costs called together a broad cross-section of National leaders members of the private housing sector (including NAHB and the NAHB Research Foundation) consumer interests academics and state and local officials This conference recognized the need of a multifaceted approach to reducing housing costs
At the same time Ernest Becker then president of NAHB and a Las Vegas builder became a leading industry proponent of affordable housing and asked the NAHB Standing Committee on Research to design and build two dwellings in Las Vegas in time for the 1979 NAHB ConventionExposition that would demonstrate cost-saving construction techniques without compromising health and safety of the occupants
The City of Las Vegas made special exceptions to the building code to allow the homes to be built and occupied Using conventional building materials and methods and a well-thought-out well-engineered plan builder Dudley A Smith then chairman of the Research Committee built the two Cost Buster homes The work drew heavily on past research done by the NAHB Research Foundation especially the eVE house
The Cost Buster project was conceived as a demonstration of modern economical construction free from unnecessary codes and regulations The project did not attempt to prove marketability customer acceptance or adapshytability to other locations It did clearly illustrate that a safe sturdy home can be built at reduced cost Direct construction cost savings amounted to about 25 percent of the cost of a conventionally built Las Vegas home of similar size
The Cost Buster homes made considerable impact on the residential buildshying community They were featured on a national television network newscast and articles were written about the homes in many of the nations leading newspapers and housing periodicals
The Cost Buster demonstration was extremely successful in what it was attempting to prove However valid criticisms of the project were offered
bull The design of the homes might prove unmarketable in many parts of the country
bull The homes were built on standard size lots in a conventionally developed subdivision
bull Cost of developed land in some parts of the country would be more of a factor in total sales price than direct construction cost
Cost Buster House
6
Land Development
Some builders had difficulty identifying with Cost Buster because of some construction techniques were not used in their areas For example the Cost Buster homes built on concrete slab foundationsfloors Some builders who built on basements or crawl space foundations dismissed the demonstration as being unusable back home Since the foundationfloor was only a part ofthe demonstration rejection of the total project on this basis seems to indicate that more builder education would be in order
Because of the interest in Cost Buster and the unresolved questions raised by the project a jOint task force was formed from NAHBs Standing Commitshytees on Research and Land Use
Members of this Task Force along with NAHB staff members and the Research Foundation went to HUD with the concept of an affordable house community-also to be built in Las Vegas-that would integrate efficient land planning cost effective construction and maketable design HUD agreed to help sponsor such an undertaking and offered its support in obtaining approvshyals as well as financing assistance The houses were to be built under the HUD Experimental Housing Program and to be insured under HUD Section 233 pursuant to Section 245 Graduated Mortgage Program Under Section 233 if any defects develop in the experimental aspects of these houses HUD guaranshytees their restitution and repair
Ernest Becker obtained a suitable site for the project and Dudley Smith developed the site and built the homes Both were instrumental in getting Las Vegas city officials to support the project Stephen Mead AlA of Des Moines Iowa was selected to design the housing units while the land plan work was assigned to the Land Use Committee The Research Foundation was charged with providing construction system advice and with monitoring of construction
The Approach SO Task Force met several times and agreed on a land plan and the dwelling designs The underlying theme of Approach SO was to develop a relatively high-density subdivision containing single-family deshytached homes duplexes and townhouses arranged in such a way so as to provide privacy along with a feeling of openness
The Approach SO site is a 5-acre rectangular tract located at the northwestern fringe of the urbanized area of Las Vegas The approximate dimensions of 335 feet by 6S5 feet include one-side of two major Las Vegas streets Smoke Ranch Road and Torrey Pines Drive which reduced the total area to be developed to about 42 acres The site was originally zoned as a residential planned development allowing S dwelling units per acre (RPD-S) Under existing standards the planned unit development (PUD) allows for maximum flexibility in residential design and land utilization The PUD may consist of attached or detached single-family units townhouses cluster units conshydominiums garden apartments or any combination thereof All development in an RPD was to be in acordance with the design standards adopted by the City Commission In the case of Approach SO the design standards were amended to provide maximum density and liveability at minimum cost
The RPD-S zoning on the 5 acres allowed for a density of S dwelling units per gross acre or 40 dwelling units The land plan adopted by the Approach SO task force provided 3S units-10 single-family attached units 14 duplex units and 14 units in clusters of threeplexes and fourplexes-all in a zero-lot-line configuration Prior to Approach SO the city of Las Vegas had never allowed multifamily and single-family detached units in the same subdivision
Widths of the 24 single-family lots varied from 3S to 42 feet and depths varied from SO to 90 feet which deviated from the 100-foot depth usually required The zero-lot-line location of these units allowed more efficient use of the lots Duplexes were attached at the lot line Triplexes and quadruplexes were clustered at the eastern end of the project with common areas adjacent on all sides
7
Plat Plan D II I 0 P 0
III 0 r II
Plot Plan
~
( I I I
l Q P [ 0
8
I
Typical Trench Detail
Approach 80 Under Construction
The road system within the 42 acres was designed to provide adequate movement for both vehicles and emergency equipment while minimizing high speed through traffic The goal was to provide each lot and common area with satisfactory access while limiting excessive pavement and right-ot-way to save land and development costs as well as reduce tuture maintenance costs Dead end streets were utilized where cul-de-sacs would normally be required saving land and paving costs Turnaround easements were provided
Jim Cashman a Riverside California builder and chairman ot the NAHB Land Use Committee assisted in negotiating approvals of the land plan Many of the deviations from Las Vegas standards were approved by the city while compromises were made on other requests Table 1 shows the usual Las Vegas land development requirements the deviations requested and the final approved designs
In addition longer than normal 4-inch house connection sewer service was allowed across public streets to main sewer lines located in easements The 20-inch minimum easement required tor 4-inch water lines was reduced to 18 inches More than one group ot townhouses were served by a single 2-inch domestic water meter where an individual meter is normally required for each unit Four-inch water mains were allowed in streets other than cul-de-sacs
The major perimeter streets required street lights conforming to the Las Vegas standards However the street lights installed in the interior of the
9
Table 1 Approach 80 Land Plan Negotiations with the City of Las Vegas
Item
R-1 lot size
Front yard set back
Side yard
Street right-of-way
Street paving
Dead end streets
Subdivision wall
Sidewalks
Sewer
Standard
60 x 120
25
0 10
60
41
Cul-de-sac
Concrete block
5 each side
8 mainline
Requested
40 x 80 45 X 75
15
0
10 5 garage
20 side 30 interior 34 entry
16 side 20 interior 24 entry
Tee section
Open sections and fencing
4 one side
4 amp6 main
Approved
40 X 90 45 X 80
15
0 10
5 garage
20 36 44
16 28 36
Break away barrier
Open sections and fencing
4 one side
4 amp6 main
)
---- --shy
Sewer and Water Plan UNO f I [ L 0 [ 0
== Z=--==
r----- ----- 7 bull a bull a -----------shy---~0--- 0 bull 1~
--- shy
( I I
I I
I
---+----+--
I
~ I I -
~ i I I i
o
- ~ 0
10
subdivision were the down type Ughting based on foot candle measure of lighting rather than maximum distance between lights
Homeowners
The Houses
I I
~i rf
Two Stud Corner with Metal Drywall Backup Clips
In order to provide on-going maintenance of Approach SO common areas and to ensure easement rights a homeowners association was formed complete with Articles of Incorporation and Declaration of Covenants Conditions and Restrictions
The 3S Approach SO units included 10 detached homes 7 duplexes 2 threeplexes and 2 fourplexes Units ranged in size from 704 square feet to 1 116 square feet One unit a detached split level contained 1 OOS square feet of finished living space and 392 square feet of expandable space in the lower level
Although the objective of Approach SO was to demonstrate low-cost marshyketable land development and construction techniques some of the demonshystrated systems were not necessarily the least costly way to build in Las Vegas For example Las Vegas has been traditionally a slab-on-grade town with very few crawl space and basement homes built in recent years The Approach SO committee decided however to build basement and crawl space homes to show alternatives in foundation and floor construction Conshystruction techniques and systems demonstrated included the following
Modular Design-Units were designed to a module of 2 feet out-to-out to reduce scrap waste and labor They were also designed to minimize length of walls and partitions
Value Engineering Techniques bull Trusses walls and floor joists were framed 24 inches on-center in line
with each other bull Two-stud corners were used with metal drywall backup clips bull Plywood box beam headers were used instead of solid wood headers
These headers created a cavity for insulation bull Windows 22112 inches wide were placed between studs 24 inches on
center to eliminate window headers bull In-line off-center spliced joists were used on one home This system
allowed use of smaller floor joists and reduced labor costs bull Single top plates were used on all walls bull Metal drywall backup clips eliminated studs as drywall nailers bull Single layer glue-nailed TampG plywood (Sturdi-floor) systems reduced
material and labor and contributed to a stiffer floor with fewer squeeks bull Single layer plywood siding eliminated sheathing and corner bracing bull Bulkheads (furred-down soffits) were eliminated over kitchen cabinets bull Amount of blocking and bracing was reduced bull Partition posts (channels) were eliminated
Construction Systems bull Reduced thickness and width of footing based on soil bearing tests bull A 2112 inch thick slab used in three slabs as demonstration bull Pressure treated wood foundations used in one crawl space and one
basement to demonstrate an alternative to cast-in-place concrete and conshycrete block foundations
bull Underfloor plenum heatingcooling system used in two homes System uses underfloor area as supply plenum eliminating ducts
bull Waterproof basement techniques demonstrated in basement homes bull Prefabricated DWV plumbing trees bull Polybutylene hot and cold water supply plumbing was demonstrated in
three homes
11
Triple Window Opening in Bearing Wall
single 2X4 op plate -+1_-
no headers
ead bloc
22 12 in~~~==tt==~----Hr--openings 1
2x4 24 in oc
II blocks -+1-
Open Soffit Overhang
-~ -t~1
-
22V2-lnch Wide Windows Between 24-lnch On-Center Studs Plywood Box Beam Headers
12
ps
f-shy
I shy
n
x r No Bulkhead Over Cabinets
Interior PartitionExterior Wall Connection
t
ISingle Layer Plywood Siding 34-lnch Tongue and Groove Single Layer APA Sturd-I-Floor
13
Exterior Wall 24 Inches On Center Single Top Plate
1== Single pp plate ~ I
[ jg fo (7~
=
l =
24-lnch On-Center In-Line Framing In-Line Off-Center Spliced Floor Joists
5
In-Line Off-Center Spliced Floor Joists
14
Light Gauge Steel Studs
shyPressure-Treated Wood Foundation
bull Light gauge steel studs were installed in one demonstration unit to show an alternative to wood interior partition framing
In most cases the systems demonstrated proved to be less costly than conventional techniques and systems In some cases the demonstrated system mayor may not be cost effective in some locales depending on local variations in material and labor costs
A house-by-house description of the demonstration units follows Seven of the units contained many of the systems that were being shown as techniques that might be usable in areas other than Las Vegas such as basements crawl spaces wood floor framing methods All 38 units contained value engineered framing sheathing Siding and other cost-reduction systems
Prefabricated Plastic DWV Plumbing Tree Polybutylene Water Supply Plumbing
15
- -
Plan 1-A one-story 782-square-foot twoshybedroom one-bath home featuring engineered framshying underfloor plenum heatingcooling pressure treated wood foundation steel interior partitions and polybutylene supply plumbing
-~ 7
bedoom -j 1---_--ir
-bedroom
garage
-shy
bHroom great room
garage
Plan 1 shy AllemIe ~middot~~_
An alternate version of Plan 1 was built to evaluate the value of certain architectural features in a small home Plan 1 contained an inset deck which provided a somewhat private outdoor space within the floor plan of the home The alternate version was designed without the inset and with the kitchen made 2 feet wider which added about 62 square feet of living area These changes will be evaluated as to marketability of the two units
16
Plan 2-A one-story 1040-square-foot three-bedroom two-bath home with value engineered framing and an underfloor plenum heatingcooling system
drooml Plan 3-A two-story 11 04-square-foot three-bedroom 1112 bath home
featuring waterproof basement construction and a lower-priced redwood lap concrete
siding
bedroom
dtnlng
conclII ptlO
living
patio bull
dining
garage
Plan 3
17
~-~ Plan 4-This plan was built as a split level and also as a slab-on-grade home The
split level version featured engineered framing in-line off center spliced floor joists pressure treated wood foundation and polybutylene supply plumbing It contained 1008 square feet of finished floor area with 392 square feet of expandable area in the lower level Rough-in for a second full bath was provided in the lower level
~~J
-~~
bbullbull oom edoomt --l l
F7 [- ~
-uplusmn~Ll n garage
The slab version of plan 4 contained 1008 square feet of living area two bedrooms and one bath It featured value engineered framing and polybutylene supply plumbing
18
Duplex-Each of the four floor plans was repeated in a duplex vershysion at least once within the subdivishysion The duplexes were basically the same with the obvious exception of firewalls included between units
UpperL
~hh _____ bull OL-
Threeplex
Triplex
11
Threeplex Under ConstructionshyThe threeplex buildings contained two two-story units and one one-story unit
19
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Introduction
Background
Although more residential construction has occurred in America during the last few decades than in any comparable period in history the United States is facing a housing crisis of alarming proportions Costs of developed land building materials and labor plus extremely high interest rates have severely limited homeownership possibilities for all but the most affluent In addition each year brings new constraints to builders and developers in the form of governmental regulations which invariably add to the total housing cost
In addition to the added construction cost of each regulation in many areas a corresponding proliferation of governmental agencies and bureaucratic procedures have created a confusing network of approvals that are extremely time consuming and costly ultimately to the home buyer Outdated conflictshying and complicated codes and standards environmental issues and reshyquirements and energy conservation issues all add to the dilemma-and to the cost-of home ownership
Originally regulations and standards were promulgated to insure a safe and healthy environment for dwelling occupants Today many regulations have little if any relationship to health and safety However good the intention however small the cost of each regulation the sum of the controls has created a substantial cost that is added to each new home built
In addition to the additional cost of regulations the average size of new homes has increased steadily each year since World War II During this period home buyers were demanding and getting larger homes with more amenities on larger lots The situation was not dissimilar to the automobile industry that was able to create mammoth luxury cars out of small economy cars in a few short years of improvements Like homebuilding the auto industry has had to contend with increased governmental regulations rapidly rising material and labor costs as well as the consumers desire for a larger product with more gadgets
Therefore the excessive cost of producing a home has become a problem with multiple causes that will require multiple solutions to correct Against this troubled backdrop Approach 80 was conceived
For years the National Association of Home Builders (NAHB) and the NAHB Research Foundation Inc have been searching for solutions to the rising cost of housing NAHB has created special committees on affordable housing the cost of governmental regulations labor and material costs and others It has sponsored research on reasonable land development standards costshyeffective energy performance guidelines construction cost control productivshyity and management techniques Through the NAHB Research House Proshygram many innovative products and techniques have been demonstrated Indeed almost all of NAHBs standing and special committees have been charged with finding ways to produce safe and healthy homes and apartments at an affordable price
The NAHB Research Foundation a wholly owned subsidiary of NAHB has also been involved with the problem of housing affordability In addition to
4
conducting much of NAHBs research efforts over the years the Research Foundation contracted with building product manufacturers governmental agencies and individual building firms in an attempt to find solutions to housing the greatest number of Americans at the least cost Under contract to the US Department of Housing and Urban Development (HUD) the Research Foundation has developed the Optimum Value Engineered (OVE)1 construcshytion system two Energy Efficient Residences (EER) and several other cost effective housing systems products and techniques Working with the buildshying products industry the Research Foundation has developed construction systems and products that improve housing value such as the Engineered 24 inches-on-center building system
HUD has worked to develop programs to make housing affordable In addition to the OVE and EER systems HUD created a National Conference on Housing Costs which resulted in the Housing Cost Reduction Demonstration and the Building Value into Housing programs HUD also has sponsored independent research on building codes updating the Minimum Property Standards (MPS) minority housing and housing for the physically handishycapped much of which was conducted by the NAHB Research Foundation Throughout the years HUD has developed financing and subsidy programs aimed at making housing affordable to a greater number of Americans
Therefore a combination of HUD NAHB and the Research Foundation was uniquely equipped to develop a housing project that would demonstrate land development and construction methods to create lower cost homes
Entrance to Approach 80
1 Reducing Home Building Costs With OVE Design and Construction Guideline 5 Superinshytendent of Documents Washington DC Government Printing Office
5
Approach 80 Concept IA 1978 HUDs National Conference on Housing Costs called together a broad cross-section of National leaders members of the private housing sector (including NAHB and the NAHB Research Foundation) consumer interests academics and state and local officials This conference recognized the need of a multifaceted approach to reducing housing costs
At the same time Ernest Becker then president of NAHB and a Las Vegas builder became a leading industry proponent of affordable housing and asked the NAHB Standing Committee on Research to design and build two dwellings in Las Vegas in time for the 1979 NAHB ConventionExposition that would demonstrate cost-saving construction techniques without compromising health and safety of the occupants
The City of Las Vegas made special exceptions to the building code to allow the homes to be built and occupied Using conventional building materials and methods and a well-thought-out well-engineered plan builder Dudley A Smith then chairman of the Research Committee built the two Cost Buster homes The work drew heavily on past research done by the NAHB Research Foundation especially the eVE house
The Cost Buster project was conceived as a demonstration of modern economical construction free from unnecessary codes and regulations The project did not attempt to prove marketability customer acceptance or adapshytability to other locations It did clearly illustrate that a safe sturdy home can be built at reduced cost Direct construction cost savings amounted to about 25 percent of the cost of a conventionally built Las Vegas home of similar size
The Cost Buster homes made considerable impact on the residential buildshying community They were featured on a national television network newscast and articles were written about the homes in many of the nations leading newspapers and housing periodicals
The Cost Buster demonstration was extremely successful in what it was attempting to prove However valid criticisms of the project were offered
bull The design of the homes might prove unmarketable in many parts of the country
bull The homes were built on standard size lots in a conventionally developed subdivision
bull Cost of developed land in some parts of the country would be more of a factor in total sales price than direct construction cost
Cost Buster House
6
Land Development
Some builders had difficulty identifying with Cost Buster because of some construction techniques were not used in their areas For example the Cost Buster homes built on concrete slab foundationsfloors Some builders who built on basements or crawl space foundations dismissed the demonstration as being unusable back home Since the foundationfloor was only a part ofthe demonstration rejection of the total project on this basis seems to indicate that more builder education would be in order
Because of the interest in Cost Buster and the unresolved questions raised by the project a jOint task force was formed from NAHBs Standing Commitshytees on Research and Land Use
Members of this Task Force along with NAHB staff members and the Research Foundation went to HUD with the concept of an affordable house community-also to be built in Las Vegas-that would integrate efficient land planning cost effective construction and maketable design HUD agreed to help sponsor such an undertaking and offered its support in obtaining approvshyals as well as financing assistance The houses were to be built under the HUD Experimental Housing Program and to be insured under HUD Section 233 pursuant to Section 245 Graduated Mortgage Program Under Section 233 if any defects develop in the experimental aspects of these houses HUD guaranshytees their restitution and repair
Ernest Becker obtained a suitable site for the project and Dudley Smith developed the site and built the homes Both were instrumental in getting Las Vegas city officials to support the project Stephen Mead AlA of Des Moines Iowa was selected to design the housing units while the land plan work was assigned to the Land Use Committee The Research Foundation was charged with providing construction system advice and with monitoring of construction
The Approach SO Task Force met several times and agreed on a land plan and the dwelling designs The underlying theme of Approach SO was to develop a relatively high-density subdivision containing single-family deshytached homes duplexes and townhouses arranged in such a way so as to provide privacy along with a feeling of openness
The Approach SO site is a 5-acre rectangular tract located at the northwestern fringe of the urbanized area of Las Vegas The approximate dimensions of 335 feet by 6S5 feet include one-side of two major Las Vegas streets Smoke Ranch Road and Torrey Pines Drive which reduced the total area to be developed to about 42 acres The site was originally zoned as a residential planned development allowing S dwelling units per acre (RPD-S) Under existing standards the planned unit development (PUD) allows for maximum flexibility in residential design and land utilization The PUD may consist of attached or detached single-family units townhouses cluster units conshydominiums garden apartments or any combination thereof All development in an RPD was to be in acordance with the design standards adopted by the City Commission In the case of Approach SO the design standards were amended to provide maximum density and liveability at minimum cost
The RPD-S zoning on the 5 acres allowed for a density of S dwelling units per gross acre or 40 dwelling units The land plan adopted by the Approach SO task force provided 3S units-10 single-family attached units 14 duplex units and 14 units in clusters of threeplexes and fourplexes-all in a zero-lot-line configuration Prior to Approach SO the city of Las Vegas had never allowed multifamily and single-family detached units in the same subdivision
Widths of the 24 single-family lots varied from 3S to 42 feet and depths varied from SO to 90 feet which deviated from the 100-foot depth usually required The zero-lot-line location of these units allowed more efficient use of the lots Duplexes were attached at the lot line Triplexes and quadruplexes were clustered at the eastern end of the project with common areas adjacent on all sides
7
Plat Plan D II I 0 P 0
III 0 r II
Plot Plan
~
( I I I
l Q P [ 0
8
I
Typical Trench Detail
Approach 80 Under Construction
The road system within the 42 acres was designed to provide adequate movement for both vehicles and emergency equipment while minimizing high speed through traffic The goal was to provide each lot and common area with satisfactory access while limiting excessive pavement and right-ot-way to save land and development costs as well as reduce tuture maintenance costs Dead end streets were utilized where cul-de-sacs would normally be required saving land and paving costs Turnaround easements were provided
Jim Cashman a Riverside California builder and chairman ot the NAHB Land Use Committee assisted in negotiating approvals of the land plan Many of the deviations from Las Vegas standards were approved by the city while compromises were made on other requests Table 1 shows the usual Las Vegas land development requirements the deviations requested and the final approved designs
In addition longer than normal 4-inch house connection sewer service was allowed across public streets to main sewer lines located in easements The 20-inch minimum easement required tor 4-inch water lines was reduced to 18 inches More than one group ot townhouses were served by a single 2-inch domestic water meter where an individual meter is normally required for each unit Four-inch water mains were allowed in streets other than cul-de-sacs
The major perimeter streets required street lights conforming to the Las Vegas standards However the street lights installed in the interior of the
9
Table 1 Approach 80 Land Plan Negotiations with the City of Las Vegas
Item
R-1 lot size
Front yard set back
Side yard
Street right-of-way
Street paving
Dead end streets
Subdivision wall
Sidewalks
Sewer
Standard
60 x 120
25
0 10
60
41
Cul-de-sac
Concrete block
5 each side
8 mainline
Requested
40 x 80 45 X 75
15
0
10 5 garage
20 side 30 interior 34 entry
16 side 20 interior 24 entry
Tee section
Open sections and fencing
4 one side
4 amp6 main
Approved
40 X 90 45 X 80
15
0 10
5 garage
20 36 44
16 28 36
Break away barrier
Open sections and fencing
4 one side
4 amp6 main
)
---- --shy
Sewer and Water Plan UNO f I [ L 0 [ 0
== Z=--==
r----- ----- 7 bull a bull a -----------shy---~0--- 0 bull 1~
--- shy
( I I
I I
I
---+----+--
I
~ I I -
~ i I I i
o
- ~ 0
10
subdivision were the down type Ughting based on foot candle measure of lighting rather than maximum distance between lights
Homeowners
The Houses
I I
~i rf
Two Stud Corner with Metal Drywall Backup Clips
In order to provide on-going maintenance of Approach SO common areas and to ensure easement rights a homeowners association was formed complete with Articles of Incorporation and Declaration of Covenants Conditions and Restrictions
The 3S Approach SO units included 10 detached homes 7 duplexes 2 threeplexes and 2 fourplexes Units ranged in size from 704 square feet to 1 116 square feet One unit a detached split level contained 1 OOS square feet of finished living space and 392 square feet of expandable space in the lower level
Although the objective of Approach SO was to demonstrate low-cost marshyketable land development and construction techniques some of the demonshystrated systems were not necessarily the least costly way to build in Las Vegas For example Las Vegas has been traditionally a slab-on-grade town with very few crawl space and basement homes built in recent years The Approach SO committee decided however to build basement and crawl space homes to show alternatives in foundation and floor construction Conshystruction techniques and systems demonstrated included the following
Modular Design-Units were designed to a module of 2 feet out-to-out to reduce scrap waste and labor They were also designed to minimize length of walls and partitions
Value Engineering Techniques bull Trusses walls and floor joists were framed 24 inches on-center in line
with each other bull Two-stud corners were used with metal drywall backup clips bull Plywood box beam headers were used instead of solid wood headers
These headers created a cavity for insulation bull Windows 22112 inches wide were placed between studs 24 inches on
center to eliminate window headers bull In-line off-center spliced joists were used on one home This system
allowed use of smaller floor joists and reduced labor costs bull Single top plates were used on all walls bull Metal drywall backup clips eliminated studs as drywall nailers bull Single layer glue-nailed TampG plywood (Sturdi-floor) systems reduced
material and labor and contributed to a stiffer floor with fewer squeeks bull Single layer plywood siding eliminated sheathing and corner bracing bull Bulkheads (furred-down soffits) were eliminated over kitchen cabinets bull Amount of blocking and bracing was reduced bull Partition posts (channels) were eliminated
Construction Systems bull Reduced thickness and width of footing based on soil bearing tests bull A 2112 inch thick slab used in three slabs as demonstration bull Pressure treated wood foundations used in one crawl space and one
basement to demonstrate an alternative to cast-in-place concrete and conshycrete block foundations
bull Underfloor plenum heatingcooling system used in two homes System uses underfloor area as supply plenum eliminating ducts
bull Waterproof basement techniques demonstrated in basement homes bull Prefabricated DWV plumbing trees bull Polybutylene hot and cold water supply plumbing was demonstrated in
three homes
11
Triple Window Opening in Bearing Wall
single 2X4 op plate -+1_-
no headers
ead bloc
22 12 in~~~==tt==~----Hr--openings 1
2x4 24 in oc
II blocks -+1-
Open Soffit Overhang
-~ -t~1
-
22V2-lnch Wide Windows Between 24-lnch On-Center Studs Plywood Box Beam Headers
12
ps
f-shy
I shy
n
x r No Bulkhead Over Cabinets
Interior PartitionExterior Wall Connection
t
ISingle Layer Plywood Siding 34-lnch Tongue and Groove Single Layer APA Sturd-I-Floor
13
Exterior Wall 24 Inches On Center Single Top Plate
1== Single pp plate ~ I
[ jg fo (7~
=
l =
24-lnch On-Center In-Line Framing In-Line Off-Center Spliced Floor Joists
5
In-Line Off-Center Spliced Floor Joists
14
Light Gauge Steel Studs
shyPressure-Treated Wood Foundation
bull Light gauge steel studs were installed in one demonstration unit to show an alternative to wood interior partition framing
In most cases the systems demonstrated proved to be less costly than conventional techniques and systems In some cases the demonstrated system mayor may not be cost effective in some locales depending on local variations in material and labor costs
A house-by-house description of the demonstration units follows Seven of the units contained many of the systems that were being shown as techniques that might be usable in areas other than Las Vegas such as basements crawl spaces wood floor framing methods All 38 units contained value engineered framing sheathing Siding and other cost-reduction systems
Prefabricated Plastic DWV Plumbing Tree Polybutylene Water Supply Plumbing
15
- -
Plan 1-A one-story 782-square-foot twoshybedroom one-bath home featuring engineered framshying underfloor plenum heatingcooling pressure treated wood foundation steel interior partitions and polybutylene supply plumbing
-~ 7
bedoom -j 1---_--ir
-bedroom
garage
-shy
bHroom great room
garage
Plan 1 shy AllemIe ~middot~~_
An alternate version of Plan 1 was built to evaluate the value of certain architectural features in a small home Plan 1 contained an inset deck which provided a somewhat private outdoor space within the floor plan of the home The alternate version was designed without the inset and with the kitchen made 2 feet wider which added about 62 square feet of living area These changes will be evaluated as to marketability of the two units
16
Plan 2-A one-story 1040-square-foot three-bedroom two-bath home with value engineered framing and an underfloor plenum heatingcooling system
drooml Plan 3-A two-story 11 04-square-foot three-bedroom 1112 bath home
featuring waterproof basement construction and a lower-priced redwood lap concrete
siding
bedroom
dtnlng
conclII ptlO
living
patio bull
dining
garage
Plan 3
17
~-~ Plan 4-This plan was built as a split level and also as a slab-on-grade home The
split level version featured engineered framing in-line off center spliced floor joists pressure treated wood foundation and polybutylene supply plumbing It contained 1008 square feet of finished floor area with 392 square feet of expandable area in the lower level Rough-in for a second full bath was provided in the lower level
~~J
-~~
bbullbull oom edoomt --l l
F7 [- ~
-uplusmn~Ll n garage
The slab version of plan 4 contained 1008 square feet of living area two bedrooms and one bath It featured value engineered framing and polybutylene supply plumbing
18
Duplex-Each of the four floor plans was repeated in a duplex vershysion at least once within the subdivishysion The duplexes were basically the same with the obvious exception of firewalls included between units
UpperL
~hh _____ bull OL-
Threeplex
Triplex
11
Threeplex Under ConstructionshyThe threeplex buildings contained two two-story units and one one-story unit
19
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
conducting much of NAHBs research efforts over the years the Research Foundation contracted with building product manufacturers governmental agencies and individual building firms in an attempt to find solutions to housing the greatest number of Americans at the least cost Under contract to the US Department of Housing and Urban Development (HUD) the Research Foundation has developed the Optimum Value Engineered (OVE)1 construcshytion system two Energy Efficient Residences (EER) and several other cost effective housing systems products and techniques Working with the buildshying products industry the Research Foundation has developed construction systems and products that improve housing value such as the Engineered 24 inches-on-center building system
HUD has worked to develop programs to make housing affordable In addition to the OVE and EER systems HUD created a National Conference on Housing Costs which resulted in the Housing Cost Reduction Demonstration and the Building Value into Housing programs HUD also has sponsored independent research on building codes updating the Minimum Property Standards (MPS) minority housing and housing for the physically handishycapped much of which was conducted by the NAHB Research Foundation Throughout the years HUD has developed financing and subsidy programs aimed at making housing affordable to a greater number of Americans
Therefore a combination of HUD NAHB and the Research Foundation was uniquely equipped to develop a housing project that would demonstrate land development and construction methods to create lower cost homes
Entrance to Approach 80
1 Reducing Home Building Costs With OVE Design and Construction Guideline 5 Superinshytendent of Documents Washington DC Government Printing Office
5
Approach 80 Concept IA 1978 HUDs National Conference on Housing Costs called together a broad cross-section of National leaders members of the private housing sector (including NAHB and the NAHB Research Foundation) consumer interests academics and state and local officials This conference recognized the need of a multifaceted approach to reducing housing costs
At the same time Ernest Becker then president of NAHB and a Las Vegas builder became a leading industry proponent of affordable housing and asked the NAHB Standing Committee on Research to design and build two dwellings in Las Vegas in time for the 1979 NAHB ConventionExposition that would demonstrate cost-saving construction techniques without compromising health and safety of the occupants
The City of Las Vegas made special exceptions to the building code to allow the homes to be built and occupied Using conventional building materials and methods and a well-thought-out well-engineered plan builder Dudley A Smith then chairman of the Research Committee built the two Cost Buster homes The work drew heavily on past research done by the NAHB Research Foundation especially the eVE house
The Cost Buster project was conceived as a demonstration of modern economical construction free from unnecessary codes and regulations The project did not attempt to prove marketability customer acceptance or adapshytability to other locations It did clearly illustrate that a safe sturdy home can be built at reduced cost Direct construction cost savings amounted to about 25 percent of the cost of a conventionally built Las Vegas home of similar size
The Cost Buster homes made considerable impact on the residential buildshying community They were featured on a national television network newscast and articles were written about the homes in many of the nations leading newspapers and housing periodicals
The Cost Buster demonstration was extremely successful in what it was attempting to prove However valid criticisms of the project were offered
bull The design of the homes might prove unmarketable in many parts of the country
bull The homes were built on standard size lots in a conventionally developed subdivision
bull Cost of developed land in some parts of the country would be more of a factor in total sales price than direct construction cost
Cost Buster House
6
Land Development
Some builders had difficulty identifying with Cost Buster because of some construction techniques were not used in their areas For example the Cost Buster homes built on concrete slab foundationsfloors Some builders who built on basements or crawl space foundations dismissed the demonstration as being unusable back home Since the foundationfloor was only a part ofthe demonstration rejection of the total project on this basis seems to indicate that more builder education would be in order
Because of the interest in Cost Buster and the unresolved questions raised by the project a jOint task force was formed from NAHBs Standing Commitshytees on Research and Land Use
Members of this Task Force along with NAHB staff members and the Research Foundation went to HUD with the concept of an affordable house community-also to be built in Las Vegas-that would integrate efficient land planning cost effective construction and maketable design HUD agreed to help sponsor such an undertaking and offered its support in obtaining approvshyals as well as financing assistance The houses were to be built under the HUD Experimental Housing Program and to be insured under HUD Section 233 pursuant to Section 245 Graduated Mortgage Program Under Section 233 if any defects develop in the experimental aspects of these houses HUD guaranshytees their restitution and repair
Ernest Becker obtained a suitable site for the project and Dudley Smith developed the site and built the homes Both were instrumental in getting Las Vegas city officials to support the project Stephen Mead AlA of Des Moines Iowa was selected to design the housing units while the land plan work was assigned to the Land Use Committee The Research Foundation was charged with providing construction system advice and with monitoring of construction
The Approach SO Task Force met several times and agreed on a land plan and the dwelling designs The underlying theme of Approach SO was to develop a relatively high-density subdivision containing single-family deshytached homes duplexes and townhouses arranged in such a way so as to provide privacy along with a feeling of openness
The Approach SO site is a 5-acre rectangular tract located at the northwestern fringe of the urbanized area of Las Vegas The approximate dimensions of 335 feet by 6S5 feet include one-side of two major Las Vegas streets Smoke Ranch Road and Torrey Pines Drive which reduced the total area to be developed to about 42 acres The site was originally zoned as a residential planned development allowing S dwelling units per acre (RPD-S) Under existing standards the planned unit development (PUD) allows for maximum flexibility in residential design and land utilization The PUD may consist of attached or detached single-family units townhouses cluster units conshydominiums garden apartments or any combination thereof All development in an RPD was to be in acordance with the design standards adopted by the City Commission In the case of Approach SO the design standards were amended to provide maximum density and liveability at minimum cost
The RPD-S zoning on the 5 acres allowed for a density of S dwelling units per gross acre or 40 dwelling units The land plan adopted by the Approach SO task force provided 3S units-10 single-family attached units 14 duplex units and 14 units in clusters of threeplexes and fourplexes-all in a zero-lot-line configuration Prior to Approach SO the city of Las Vegas had never allowed multifamily and single-family detached units in the same subdivision
Widths of the 24 single-family lots varied from 3S to 42 feet and depths varied from SO to 90 feet which deviated from the 100-foot depth usually required The zero-lot-line location of these units allowed more efficient use of the lots Duplexes were attached at the lot line Triplexes and quadruplexes were clustered at the eastern end of the project with common areas adjacent on all sides
7
Plat Plan D II I 0 P 0
III 0 r II
Plot Plan
~
( I I I
l Q P [ 0
8
I
Typical Trench Detail
Approach 80 Under Construction
The road system within the 42 acres was designed to provide adequate movement for both vehicles and emergency equipment while minimizing high speed through traffic The goal was to provide each lot and common area with satisfactory access while limiting excessive pavement and right-ot-way to save land and development costs as well as reduce tuture maintenance costs Dead end streets were utilized where cul-de-sacs would normally be required saving land and paving costs Turnaround easements were provided
Jim Cashman a Riverside California builder and chairman ot the NAHB Land Use Committee assisted in negotiating approvals of the land plan Many of the deviations from Las Vegas standards were approved by the city while compromises were made on other requests Table 1 shows the usual Las Vegas land development requirements the deviations requested and the final approved designs
In addition longer than normal 4-inch house connection sewer service was allowed across public streets to main sewer lines located in easements The 20-inch minimum easement required tor 4-inch water lines was reduced to 18 inches More than one group ot townhouses were served by a single 2-inch domestic water meter where an individual meter is normally required for each unit Four-inch water mains were allowed in streets other than cul-de-sacs
The major perimeter streets required street lights conforming to the Las Vegas standards However the street lights installed in the interior of the
9
Table 1 Approach 80 Land Plan Negotiations with the City of Las Vegas
Item
R-1 lot size
Front yard set back
Side yard
Street right-of-way
Street paving
Dead end streets
Subdivision wall
Sidewalks
Sewer
Standard
60 x 120
25
0 10
60
41
Cul-de-sac
Concrete block
5 each side
8 mainline
Requested
40 x 80 45 X 75
15
0
10 5 garage
20 side 30 interior 34 entry
16 side 20 interior 24 entry
Tee section
Open sections and fencing
4 one side
4 amp6 main
Approved
40 X 90 45 X 80
15
0 10
5 garage
20 36 44
16 28 36
Break away barrier
Open sections and fencing
4 one side
4 amp6 main
)
---- --shy
Sewer and Water Plan UNO f I [ L 0 [ 0
== Z=--==
r----- ----- 7 bull a bull a -----------shy---~0--- 0 bull 1~
--- shy
( I I
I I
I
---+----+--
I
~ I I -
~ i I I i
o
- ~ 0
10
subdivision were the down type Ughting based on foot candle measure of lighting rather than maximum distance between lights
Homeowners
The Houses
I I
~i rf
Two Stud Corner with Metal Drywall Backup Clips
In order to provide on-going maintenance of Approach SO common areas and to ensure easement rights a homeowners association was formed complete with Articles of Incorporation and Declaration of Covenants Conditions and Restrictions
The 3S Approach SO units included 10 detached homes 7 duplexes 2 threeplexes and 2 fourplexes Units ranged in size from 704 square feet to 1 116 square feet One unit a detached split level contained 1 OOS square feet of finished living space and 392 square feet of expandable space in the lower level
Although the objective of Approach SO was to demonstrate low-cost marshyketable land development and construction techniques some of the demonshystrated systems were not necessarily the least costly way to build in Las Vegas For example Las Vegas has been traditionally a slab-on-grade town with very few crawl space and basement homes built in recent years The Approach SO committee decided however to build basement and crawl space homes to show alternatives in foundation and floor construction Conshystruction techniques and systems demonstrated included the following
Modular Design-Units were designed to a module of 2 feet out-to-out to reduce scrap waste and labor They were also designed to minimize length of walls and partitions
Value Engineering Techniques bull Trusses walls and floor joists were framed 24 inches on-center in line
with each other bull Two-stud corners were used with metal drywall backup clips bull Plywood box beam headers were used instead of solid wood headers
These headers created a cavity for insulation bull Windows 22112 inches wide were placed between studs 24 inches on
center to eliminate window headers bull In-line off-center spliced joists were used on one home This system
allowed use of smaller floor joists and reduced labor costs bull Single top plates were used on all walls bull Metal drywall backup clips eliminated studs as drywall nailers bull Single layer glue-nailed TampG plywood (Sturdi-floor) systems reduced
material and labor and contributed to a stiffer floor with fewer squeeks bull Single layer plywood siding eliminated sheathing and corner bracing bull Bulkheads (furred-down soffits) were eliminated over kitchen cabinets bull Amount of blocking and bracing was reduced bull Partition posts (channels) were eliminated
Construction Systems bull Reduced thickness and width of footing based on soil bearing tests bull A 2112 inch thick slab used in three slabs as demonstration bull Pressure treated wood foundations used in one crawl space and one
basement to demonstrate an alternative to cast-in-place concrete and conshycrete block foundations
bull Underfloor plenum heatingcooling system used in two homes System uses underfloor area as supply plenum eliminating ducts
bull Waterproof basement techniques demonstrated in basement homes bull Prefabricated DWV plumbing trees bull Polybutylene hot and cold water supply plumbing was demonstrated in
three homes
11
Triple Window Opening in Bearing Wall
single 2X4 op plate -+1_-
no headers
ead bloc
22 12 in~~~==tt==~----Hr--openings 1
2x4 24 in oc
II blocks -+1-
Open Soffit Overhang
-~ -t~1
-
22V2-lnch Wide Windows Between 24-lnch On-Center Studs Plywood Box Beam Headers
12
ps
f-shy
I shy
n
x r No Bulkhead Over Cabinets
Interior PartitionExterior Wall Connection
t
ISingle Layer Plywood Siding 34-lnch Tongue and Groove Single Layer APA Sturd-I-Floor
13
Exterior Wall 24 Inches On Center Single Top Plate
1== Single pp plate ~ I
[ jg fo (7~
=
l =
24-lnch On-Center In-Line Framing In-Line Off-Center Spliced Floor Joists
5
In-Line Off-Center Spliced Floor Joists
14
Light Gauge Steel Studs
shyPressure-Treated Wood Foundation
bull Light gauge steel studs were installed in one demonstration unit to show an alternative to wood interior partition framing
In most cases the systems demonstrated proved to be less costly than conventional techniques and systems In some cases the demonstrated system mayor may not be cost effective in some locales depending on local variations in material and labor costs
A house-by-house description of the demonstration units follows Seven of the units contained many of the systems that were being shown as techniques that might be usable in areas other than Las Vegas such as basements crawl spaces wood floor framing methods All 38 units contained value engineered framing sheathing Siding and other cost-reduction systems
Prefabricated Plastic DWV Plumbing Tree Polybutylene Water Supply Plumbing
15
- -
Plan 1-A one-story 782-square-foot twoshybedroom one-bath home featuring engineered framshying underfloor plenum heatingcooling pressure treated wood foundation steel interior partitions and polybutylene supply plumbing
-~ 7
bedoom -j 1---_--ir
-bedroom
garage
-shy
bHroom great room
garage
Plan 1 shy AllemIe ~middot~~_
An alternate version of Plan 1 was built to evaluate the value of certain architectural features in a small home Plan 1 contained an inset deck which provided a somewhat private outdoor space within the floor plan of the home The alternate version was designed without the inset and with the kitchen made 2 feet wider which added about 62 square feet of living area These changes will be evaluated as to marketability of the two units
16
Plan 2-A one-story 1040-square-foot three-bedroom two-bath home with value engineered framing and an underfloor plenum heatingcooling system
drooml Plan 3-A two-story 11 04-square-foot three-bedroom 1112 bath home
featuring waterproof basement construction and a lower-priced redwood lap concrete
siding
bedroom
dtnlng
conclII ptlO
living
patio bull
dining
garage
Plan 3
17
~-~ Plan 4-This plan was built as a split level and also as a slab-on-grade home The
split level version featured engineered framing in-line off center spliced floor joists pressure treated wood foundation and polybutylene supply plumbing It contained 1008 square feet of finished floor area with 392 square feet of expandable area in the lower level Rough-in for a second full bath was provided in the lower level
~~J
-~~
bbullbull oom edoomt --l l
F7 [- ~
-uplusmn~Ll n garage
The slab version of plan 4 contained 1008 square feet of living area two bedrooms and one bath It featured value engineered framing and polybutylene supply plumbing
18
Duplex-Each of the four floor plans was repeated in a duplex vershysion at least once within the subdivishysion The duplexes were basically the same with the obvious exception of firewalls included between units
UpperL
~hh _____ bull OL-
Threeplex
Triplex
11
Threeplex Under ConstructionshyThe threeplex buildings contained two two-story units and one one-story unit
19
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Approach 80 Concept IA 1978 HUDs National Conference on Housing Costs called together a broad cross-section of National leaders members of the private housing sector (including NAHB and the NAHB Research Foundation) consumer interests academics and state and local officials This conference recognized the need of a multifaceted approach to reducing housing costs
At the same time Ernest Becker then president of NAHB and a Las Vegas builder became a leading industry proponent of affordable housing and asked the NAHB Standing Committee on Research to design and build two dwellings in Las Vegas in time for the 1979 NAHB ConventionExposition that would demonstrate cost-saving construction techniques without compromising health and safety of the occupants
The City of Las Vegas made special exceptions to the building code to allow the homes to be built and occupied Using conventional building materials and methods and a well-thought-out well-engineered plan builder Dudley A Smith then chairman of the Research Committee built the two Cost Buster homes The work drew heavily on past research done by the NAHB Research Foundation especially the eVE house
The Cost Buster project was conceived as a demonstration of modern economical construction free from unnecessary codes and regulations The project did not attempt to prove marketability customer acceptance or adapshytability to other locations It did clearly illustrate that a safe sturdy home can be built at reduced cost Direct construction cost savings amounted to about 25 percent of the cost of a conventionally built Las Vegas home of similar size
The Cost Buster homes made considerable impact on the residential buildshying community They were featured on a national television network newscast and articles were written about the homes in many of the nations leading newspapers and housing periodicals
The Cost Buster demonstration was extremely successful in what it was attempting to prove However valid criticisms of the project were offered
bull The design of the homes might prove unmarketable in many parts of the country
bull The homes were built on standard size lots in a conventionally developed subdivision
bull Cost of developed land in some parts of the country would be more of a factor in total sales price than direct construction cost
Cost Buster House
6
Land Development
Some builders had difficulty identifying with Cost Buster because of some construction techniques were not used in their areas For example the Cost Buster homes built on concrete slab foundationsfloors Some builders who built on basements or crawl space foundations dismissed the demonstration as being unusable back home Since the foundationfloor was only a part ofthe demonstration rejection of the total project on this basis seems to indicate that more builder education would be in order
Because of the interest in Cost Buster and the unresolved questions raised by the project a jOint task force was formed from NAHBs Standing Commitshytees on Research and Land Use
Members of this Task Force along with NAHB staff members and the Research Foundation went to HUD with the concept of an affordable house community-also to be built in Las Vegas-that would integrate efficient land planning cost effective construction and maketable design HUD agreed to help sponsor such an undertaking and offered its support in obtaining approvshyals as well as financing assistance The houses were to be built under the HUD Experimental Housing Program and to be insured under HUD Section 233 pursuant to Section 245 Graduated Mortgage Program Under Section 233 if any defects develop in the experimental aspects of these houses HUD guaranshytees their restitution and repair
Ernest Becker obtained a suitable site for the project and Dudley Smith developed the site and built the homes Both were instrumental in getting Las Vegas city officials to support the project Stephen Mead AlA of Des Moines Iowa was selected to design the housing units while the land plan work was assigned to the Land Use Committee The Research Foundation was charged with providing construction system advice and with monitoring of construction
The Approach SO Task Force met several times and agreed on a land plan and the dwelling designs The underlying theme of Approach SO was to develop a relatively high-density subdivision containing single-family deshytached homes duplexes and townhouses arranged in such a way so as to provide privacy along with a feeling of openness
The Approach SO site is a 5-acre rectangular tract located at the northwestern fringe of the urbanized area of Las Vegas The approximate dimensions of 335 feet by 6S5 feet include one-side of two major Las Vegas streets Smoke Ranch Road and Torrey Pines Drive which reduced the total area to be developed to about 42 acres The site was originally zoned as a residential planned development allowing S dwelling units per acre (RPD-S) Under existing standards the planned unit development (PUD) allows for maximum flexibility in residential design and land utilization The PUD may consist of attached or detached single-family units townhouses cluster units conshydominiums garden apartments or any combination thereof All development in an RPD was to be in acordance with the design standards adopted by the City Commission In the case of Approach SO the design standards were amended to provide maximum density and liveability at minimum cost
The RPD-S zoning on the 5 acres allowed for a density of S dwelling units per gross acre or 40 dwelling units The land plan adopted by the Approach SO task force provided 3S units-10 single-family attached units 14 duplex units and 14 units in clusters of threeplexes and fourplexes-all in a zero-lot-line configuration Prior to Approach SO the city of Las Vegas had never allowed multifamily and single-family detached units in the same subdivision
Widths of the 24 single-family lots varied from 3S to 42 feet and depths varied from SO to 90 feet which deviated from the 100-foot depth usually required The zero-lot-line location of these units allowed more efficient use of the lots Duplexes were attached at the lot line Triplexes and quadruplexes were clustered at the eastern end of the project with common areas adjacent on all sides
7
Plat Plan D II I 0 P 0
III 0 r II
Plot Plan
~
( I I I
l Q P [ 0
8
I
Typical Trench Detail
Approach 80 Under Construction
The road system within the 42 acres was designed to provide adequate movement for both vehicles and emergency equipment while minimizing high speed through traffic The goal was to provide each lot and common area with satisfactory access while limiting excessive pavement and right-ot-way to save land and development costs as well as reduce tuture maintenance costs Dead end streets were utilized where cul-de-sacs would normally be required saving land and paving costs Turnaround easements were provided
Jim Cashman a Riverside California builder and chairman ot the NAHB Land Use Committee assisted in negotiating approvals of the land plan Many of the deviations from Las Vegas standards were approved by the city while compromises were made on other requests Table 1 shows the usual Las Vegas land development requirements the deviations requested and the final approved designs
In addition longer than normal 4-inch house connection sewer service was allowed across public streets to main sewer lines located in easements The 20-inch minimum easement required tor 4-inch water lines was reduced to 18 inches More than one group ot townhouses were served by a single 2-inch domestic water meter where an individual meter is normally required for each unit Four-inch water mains were allowed in streets other than cul-de-sacs
The major perimeter streets required street lights conforming to the Las Vegas standards However the street lights installed in the interior of the
9
Table 1 Approach 80 Land Plan Negotiations with the City of Las Vegas
Item
R-1 lot size
Front yard set back
Side yard
Street right-of-way
Street paving
Dead end streets
Subdivision wall
Sidewalks
Sewer
Standard
60 x 120
25
0 10
60
41
Cul-de-sac
Concrete block
5 each side
8 mainline
Requested
40 x 80 45 X 75
15
0
10 5 garage
20 side 30 interior 34 entry
16 side 20 interior 24 entry
Tee section
Open sections and fencing
4 one side
4 amp6 main
Approved
40 X 90 45 X 80
15
0 10
5 garage
20 36 44
16 28 36
Break away barrier
Open sections and fencing
4 one side
4 amp6 main
)
---- --shy
Sewer and Water Plan UNO f I [ L 0 [ 0
== Z=--==
r----- ----- 7 bull a bull a -----------shy---~0--- 0 bull 1~
--- shy
( I I
I I
I
---+----+--
I
~ I I -
~ i I I i
o
- ~ 0
10
subdivision were the down type Ughting based on foot candle measure of lighting rather than maximum distance between lights
Homeowners
The Houses
I I
~i rf
Two Stud Corner with Metal Drywall Backup Clips
In order to provide on-going maintenance of Approach SO common areas and to ensure easement rights a homeowners association was formed complete with Articles of Incorporation and Declaration of Covenants Conditions and Restrictions
The 3S Approach SO units included 10 detached homes 7 duplexes 2 threeplexes and 2 fourplexes Units ranged in size from 704 square feet to 1 116 square feet One unit a detached split level contained 1 OOS square feet of finished living space and 392 square feet of expandable space in the lower level
Although the objective of Approach SO was to demonstrate low-cost marshyketable land development and construction techniques some of the demonshystrated systems were not necessarily the least costly way to build in Las Vegas For example Las Vegas has been traditionally a slab-on-grade town with very few crawl space and basement homes built in recent years The Approach SO committee decided however to build basement and crawl space homes to show alternatives in foundation and floor construction Conshystruction techniques and systems demonstrated included the following
Modular Design-Units were designed to a module of 2 feet out-to-out to reduce scrap waste and labor They were also designed to minimize length of walls and partitions
Value Engineering Techniques bull Trusses walls and floor joists were framed 24 inches on-center in line
with each other bull Two-stud corners were used with metal drywall backup clips bull Plywood box beam headers were used instead of solid wood headers
These headers created a cavity for insulation bull Windows 22112 inches wide were placed between studs 24 inches on
center to eliminate window headers bull In-line off-center spliced joists were used on one home This system
allowed use of smaller floor joists and reduced labor costs bull Single top plates were used on all walls bull Metal drywall backup clips eliminated studs as drywall nailers bull Single layer glue-nailed TampG plywood (Sturdi-floor) systems reduced
material and labor and contributed to a stiffer floor with fewer squeeks bull Single layer plywood siding eliminated sheathing and corner bracing bull Bulkheads (furred-down soffits) were eliminated over kitchen cabinets bull Amount of blocking and bracing was reduced bull Partition posts (channels) were eliminated
Construction Systems bull Reduced thickness and width of footing based on soil bearing tests bull A 2112 inch thick slab used in three slabs as demonstration bull Pressure treated wood foundations used in one crawl space and one
basement to demonstrate an alternative to cast-in-place concrete and conshycrete block foundations
bull Underfloor plenum heatingcooling system used in two homes System uses underfloor area as supply plenum eliminating ducts
bull Waterproof basement techniques demonstrated in basement homes bull Prefabricated DWV plumbing trees bull Polybutylene hot and cold water supply plumbing was demonstrated in
three homes
11
Triple Window Opening in Bearing Wall
single 2X4 op plate -+1_-
no headers
ead bloc
22 12 in~~~==tt==~----Hr--openings 1
2x4 24 in oc
II blocks -+1-
Open Soffit Overhang
-~ -t~1
-
22V2-lnch Wide Windows Between 24-lnch On-Center Studs Plywood Box Beam Headers
12
ps
f-shy
I shy
n
x r No Bulkhead Over Cabinets
Interior PartitionExterior Wall Connection
t
ISingle Layer Plywood Siding 34-lnch Tongue and Groove Single Layer APA Sturd-I-Floor
13
Exterior Wall 24 Inches On Center Single Top Plate
1== Single pp plate ~ I
[ jg fo (7~
=
l =
24-lnch On-Center In-Line Framing In-Line Off-Center Spliced Floor Joists
5
In-Line Off-Center Spliced Floor Joists
14
Light Gauge Steel Studs
shyPressure-Treated Wood Foundation
bull Light gauge steel studs were installed in one demonstration unit to show an alternative to wood interior partition framing
In most cases the systems demonstrated proved to be less costly than conventional techniques and systems In some cases the demonstrated system mayor may not be cost effective in some locales depending on local variations in material and labor costs
A house-by-house description of the demonstration units follows Seven of the units contained many of the systems that were being shown as techniques that might be usable in areas other than Las Vegas such as basements crawl spaces wood floor framing methods All 38 units contained value engineered framing sheathing Siding and other cost-reduction systems
Prefabricated Plastic DWV Plumbing Tree Polybutylene Water Supply Plumbing
15
- -
Plan 1-A one-story 782-square-foot twoshybedroom one-bath home featuring engineered framshying underfloor plenum heatingcooling pressure treated wood foundation steel interior partitions and polybutylene supply plumbing
-~ 7
bedoom -j 1---_--ir
-bedroom
garage
-shy
bHroom great room
garage
Plan 1 shy AllemIe ~middot~~_
An alternate version of Plan 1 was built to evaluate the value of certain architectural features in a small home Plan 1 contained an inset deck which provided a somewhat private outdoor space within the floor plan of the home The alternate version was designed without the inset and with the kitchen made 2 feet wider which added about 62 square feet of living area These changes will be evaluated as to marketability of the two units
16
Plan 2-A one-story 1040-square-foot three-bedroom two-bath home with value engineered framing and an underfloor plenum heatingcooling system
drooml Plan 3-A two-story 11 04-square-foot three-bedroom 1112 bath home
featuring waterproof basement construction and a lower-priced redwood lap concrete
siding
bedroom
dtnlng
conclII ptlO
living
patio bull
dining
garage
Plan 3
17
~-~ Plan 4-This plan was built as a split level and also as a slab-on-grade home The
split level version featured engineered framing in-line off center spliced floor joists pressure treated wood foundation and polybutylene supply plumbing It contained 1008 square feet of finished floor area with 392 square feet of expandable area in the lower level Rough-in for a second full bath was provided in the lower level
~~J
-~~
bbullbull oom edoomt --l l
F7 [- ~
-uplusmn~Ll n garage
The slab version of plan 4 contained 1008 square feet of living area two bedrooms and one bath It featured value engineered framing and polybutylene supply plumbing
18
Duplex-Each of the four floor plans was repeated in a duplex vershysion at least once within the subdivishysion The duplexes were basically the same with the obvious exception of firewalls included between units
UpperL
~hh _____ bull OL-
Threeplex
Triplex
11
Threeplex Under ConstructionshyThe threeplex buildings contained two two-story units and one one-story unit
19
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Land Development
Some builders had difficulty identifying with Cost Buster because of some construction techniques were not used in their areas For example the Cost Buster homes built on concrete slab foundationsfloors Some builders who built on basements or crawl space foundations dismissed the demonstration as being unusable back home Since the foundationfloor was only a part ofthe demonstration rejection of the total project on this basis seems to indicate that more builder education would be in order
Because of the interest in Cost Buster and the unresolved questions raised by the project a jOint task force was formed from NAHBs Standing Commitshytees on Research and Land Use
Members of this Task Force along with NAHB staff members and the Research Foundation went to HUD with the concept of an affordable house community-also to be built in Las Vegas-that would integrate efficient land planning cost effective construction and maketable design HUD agreed to help sponsor such an undertaking and offered its support in obtaining approvshyals as well as financing assistance The houses were to be built under the HUD Experimental Housing Program and to be insured under HUD Section 233 pursuant to Section 245 Graduated Mortgage Program Under Section 233 if any defects develop in the experimental aspects of these houses HUD guaranshytees their restitution and repair
Ernest Becker obtained a suitable site for the project and Dudley Smith developed the site and built the homes Both were instrumental in getting Las Vegas city officials to support the project Stephen Mead AlA of Des Moines Iowa was selected to design the housing units while the land plan work was assigned to the Land Use Committee The Research Foundation was charged with providing construction system advice and with monitoring of construction
The Approach SO Task Force met several times and agreed on a land plan and the dwelling designs The underlying theme of Approach SO was to develop a relatively high-density subdivision containing single-family deshytached homes duplexes and townhouses arranged in such a way so as to provide privacy along with a feeling of openness
The Approach SO site is a 5-acre rectangular tract located at the northwestern fringe of the urbanized area of Las Vegas The approximate dimensions of 335 feet by 6S5 feet include one-side of two major Las Vegas streets Smoke Ranch Road and Torrey Pines Drive which reduced the total area to be developed to about 42 acres The site was originally zoned as a residential planned development allowing S dwelling units per acre (RPD-S) Under existing standards the planned unit development (PUD) allows for maximum flexibility in residential design and land utilization The PUD may consist of attached or detached single-family units townhouses cluster units conshydominiums garden apartments or any combination thereof All development in an RPD was to be in acordance with the design standards adopted by the City Commission In the case of Approach SO the design standards were amended to provide maximum density and liveability at minimum cost
The RPD-S zoning on the 5 acres allowed for a density of S dwelling units per gross acre or 40 dwelling units The land plan adopted by the Approach SO task force provided 3S units-10 single-family attached units 14 duplex units and 14 units in clusters of threeplexes and fourplexes-all in a zero-lot-line configuration Prior to Approach SO the city of Las Vegas had never allowed multifamily and single-family detached units in the same subdivision
Widths of the 24 single-family lots varied from 3S to 42 feet and depths varied from SO to 90 feet which deviated from the 100-foot depth usually required The zero-lot-line location of these units allowed more efficient use of the lots Duplexes were attached at the lot line Triplexes and quadruplexes were clustered at the eastern end of the project with common areas adjacent on all sides
7
Plat Plan D II I 0 P 0
III 0 r II
Plot Plan
~
( I I I
l Q P [ 0
8
I
Typical Trench Detail
Approach 80 Under Construction
The road system within the 42 acres was designed to provide adequate movement for both vehicles and emergency equipment while minimizing high speed through traffic The goal was to provide each lot and common area with satisfactory access while limiting excessive pavement and right-ot-way to save land and development costs as well as reduce tuture maintenance costs Dead end streets were utilized where cul-de-sacs would normally be required saving land and paving costs Turnaround easements were provided
Jim Cashman a Riverside California builder and chairman ot the NAHB Land Use Committee assisted in negotiating approvals of the land plan Many of the deviations from Las Vegas standards were approved by the city while compromises were made on other requests Table 1 shows the usual Las Vegas land development requirements the deviations requested and the final approved designs
In addition longer than normal 4-inch house connection sewer service was allowed across public streets to main sewer lines located in easements The 20-inch minimum easement required tor 4-inch water lines was reduced to 18 inches More than one group ot townhouses were served by a single 2-inch domestic water meter where an individual meter is normally required for each unit Four-inch water mains were allowed in streets other than cul-de-sacs
The major perimeter streets required street lights conforming to the Las Vegas standards However the street lights installed in the interior of the
9
Table 1 Approach 80 Land Plan Negotiations with the City of Las Vegas
Item
R-1 lot size
Front yard set back
Side yard
Street right-of-way
Street paving
Dead end streets
Subdivision wall
Sidewalks
Sewer
Standard
60 x 120
25
0 10
60
41
Cul-de-sac
Concrete block
5 each side
8 mainline
Requested
40 x 80 45 X 75
15
0
10 5 garage
20 side 30 interior 34 entry
16 side 20 interior 24 entry
Tee section
Open sections and fencing
4 one side
4 amp6 main
Approved
40 X 90 45 X 80
15
0 10
5 garage
20 36 44
16 28 36
Break away barrier
Open sections and fencing
4 one side
4 amp6 main
)
---- --shy
Sewer and Water Plan UNO f I [ L 0 [ 0
== Z=--==
r----- ----- 7 bull a bull a -----------shy---~0--- 0 bull 1~
--- shy
( I I
I I
I
---+----+--
I
~ I I -
~ i I I i
o
- ~ 0
10
subdivision were the down type Ughting based on foot candle measure of lighting rather than maximum distance between lights
Homeowners
The Houses
I I
~i rf
Two Stud Corner with Metal Drywall Backup Clips
In order to provide on-going maintenance of Approach SO common areas and to ensure easement rights a homeowners association was formed complete with Articles of Incorporation and Declaration of Covenants Conditions and Restrictions
The 3S Approach SO units included 10 detached homes 7 duplexes 2 threeplexes and 2 fourplexes Units ranged in size from 704 square feet to 1 116 square feet One unit a detached split level contained 1 OOS square feet of finished living space and 392 square feet of expandable space in the lower level
Although the objective of Approach SO was to demonstrate low-cost marshyketable land development and construction techniques some of the demonshystrated systems were not necessarily the least costly way to build in Las Vegas For example Las Vegas has been traditionally a slab-on-grade town with very few crawl space and basement homes built in recent years The Approach SO committee decided however to build basement and crawl space homes to show alternatives in foundation and floor construction Conshystruction techniques and systems demonstrated included the following
Modular Design-Units were designed to a module of 2 feet out-to-out to reduce scrap waste and labor They were also designed to minimize length of walls and partitions
Value Engineering Techniques bull Trusses walls and floor joists were framed 24 inches on-center in line
with each other bull Two-stud corners were used with metal drywall backup clips bull Plywood box beam headers were used instead of solid wood headers
These headers created a cavity for insulation bull Windows 22112 inches wide were placed between studs 24 inches on
center to eliminate window headers bull In-line off-center spliced joists were used on one home This system
allowed use of smaller floor joists and reduced labor costs bull Single top plates were used on all walls bull Metal drywall backup clips eliminated studs as drywall nailers bull Single layer glue-nailed TampG plywood (Sturdi-floor) systems reduced
material and labor and contributed to a stiffer floor with fewer squeeks bull Single layer plywood siding eliminated sheathing and corner bracing bull Bulkheads (furred-down soffits) were eliminated over kitchen cabinets bull Amount of blocking and bracing was reduced bull Partition posts (channels) were eliminated
Construction Systems bull Reduced thickness and width of footing based on soil bearing tests bull A 2112 inch thick slab used in three slabs as demonstration bull Pressure treated wood foundations used in one crawl space and one
basement to demonstrate an alternative to cast-in-place concrete and conshycrete block foundations
bull Underfloor plenum heatingcooling system used in two homes System uses underfloor area as supply plenum eliminating ducts
bull Waterproof basement techniques demonstrated in basement homes bull Prefabricated DWV plumbing trees bull Polybutylene hot and cold water supply plumbing was demonstrated in
three homes
11
Triple Window Opening in Bearing Wall
single 2X4 op plate -+1_-
no headers
ead bloc
22 12 in~~~==tt==~----Hr--openings 1
2x4 24 in oc
II blocks -+1-
Open Soffit Overhang
-~ -t~1
-
22V2-lnch Wide Windows Between 24-lnch On-Center Studs Plywood Box Beam Headers
12
ps
f-shy
I shy
n
x r No Bulkhead Over Cabinets
Interior PartitionExterior Wall Connection
t
ISingle Layer Plywood Siding 34-lnch Tongue and Groove Single Layer APA Sturd-I-Floor
13
Exterior Wall 24 Inches On Center Single Top Plate
1== Single pp plate ~ I
[ jg fo (7~
=
l =
24-lnch On-Center In-Line Framing In-Line Off-Center Spliced Floor Joists
5
In-Line Off-Center Spliced Floor Joists
14
Light Gauge Steel Studs
shyPressure-Treated Wood Foundation
bull Light gauge steel studs were installed in one demonstration unit to show an alternative to wood interior partition framing
In most cases the systems demonstrated proved to be less costly than conventional techniques and systems In some cases the demonstrated system mayor may not be cost effective in some locales depending on local variations in material and labor costs
A house-by-house description of the demonstration units follows Seven of the units contained many of the systems that were being shown as techniques that might be usable in areas other than Las Vegas such as basements crawl spaces wood floor framing methods All 38 units contained value engineered framing sheathing Siding and other cost-reduction systems
Prefabricated Plastic DWV Plumbing Tree Polybutylene Water Supply Plumbing
15
- -
Plan 1-A one-story 782-square-foot twoshybedroom one-bath home featuring engineered framshying underfloor plenum heatingcooling pressure treated wood foundation steel interior partitions and polybutylene supply plumbing
-~ 7
bedoom -j 1---_--ir
-bedroom
garage
-shy
bHroom great room
garage
Plan 1 shy AllemIe ~middot~~_
An alternate version of Plan 1 was built to evaluate the value of certain architectural features in a small home Plan 1 contained an inset deck which provided a somewhat private outdoor space within the floor plan of the home The alternate version was designed without the inset and with the kitchen made 2 feet wider which added about 62 square feet of living area These changes will be evaluated as to marketability of the two units
16
Plan 2-A one-story 1040-square-foot three-bedroom two-bath home with value engineered framing and an underfloor plenum heatingcooling system
drooml Plan 3-A two-story 11 04-square-foot three-bedroom 1112 bath home
featuring waterproof basement construction and a lower-priced redwood lap concrete
siding
bedroom
dtnlng
conclII ptlO
living
patio bull
dining
garage
Plan 3
17
~-~ Plan 4-This plan was built as a split level and also as a slab-on-grade home The
split level version featured engineered framing in-line off center spliced floor joists pressure treated wood foundation and polybutylene supply plumbing It contained 1008 square feet of finished floor area with 392 square feet of expandable area in the lower level Rough-in for a second full bath was provided in the lower level
~~J
-~~
bbullbull oom edoomt --l l
F7 [- ~
-uplusmn~Ll n garage
The slab version of plan 4 contained 1008 square feet of living area two bedrooms and one bath It featured value engineered framing and polybutylene supply plumbing
18
Duplex-Each of the four floor plans was repeated in a duplex vershysion at least once within the subdivishysion The duplexes were basically the same with the obvious exception of firewalls included between units
UpperL
~hh _____ bull OL-
Threeplex
Triplex
11
Threeplex Under ConstructionshyThe threeplex buildings contained two two-story units and one one-story unit
19
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Plat Plan D II I 0 P 0
III 0 r II
Plot Plan
~
( I I I
l Q P [ 0
8
I
Typical Trench Detail
Approach 80 Under Construction
The road system within the 42 acres was designed to provide adequate movement for both vehicles and emergency equipment while minimizing high speed through traffic The goal was to provide each lot and common area with satisfactory access while limiting excessive pavement and right-ot-way to save land and development costs as well as reduce tuture maintenance costs Dead end streets were utilized where cul-de-sacs would normally be required saving land and paving costs Turnaround easements were provided
Jim Cashman a Riverside California builder and chairman ot the NAHB Land Use Committee assisted in negotiating approvals of the land plan Many of the deviations from Las Vegas standards were approved by the city while compromises were made on other requests Table 1 shows the usual Las Vegas land development requirements the deviations requested and the final approved designs
In addition longer than normal 4-inch house connection sewer service was allowed across public streets to main sewer lines located in easements The 20-inch minimum easement required tor 4-inch water lines was reduced to 18 inches More than one group ot townhouses were served by a single 2-inch domestic water meter where an individual meter is normally required for each unit Four-inch water mains were allowed in streets other than cul-de-sacs
The major perimeter streets required street lights conforming to the Las Vegas standards However the street lights installed in the interior of the
9
Table 1 Approach 80 Land Plan Negotiations with the City of Las Vegas
Item
R-1 lot size
Front yard set back
Side yard
Street right-of-way
Street paving
Dead end streets
Subdivision wall
Sidewalks
Sewer
Standard
60 x 120
25
0 10
60
41
Cul-de-sac
Concrete block
5 each side
8 mainline
Requested
40 x 80 45 X 75
15
0
10 5 garage
20 side 30 interior 34 entry
16 side 20 interior 24 entry
Tee section
Open sections and fencing
4 one side
4 amp6 main
Approved
40 X 90 45 X 80
15
0 10
5 garage
20 36 44
16 28 36
Break away barrier
Open sections and fencing
4 one side
4 amp6 main
)
---- --shy
Sewer and Water Plan UNO f I [ L 0 [ 0
== Z=--==
r----- ----- 7 bull a bull a -----------shy---~0--- 0 bull 1~
--- shy
( I I
I I
I
---+----+--
I
~ I I -
~ i I I i
o
- ~ 0
10
subdivision were the down type Ughting based on foot candle measure of lighting rather than maximum distance between lights
Homeowners
The Houses
I I
~i rf
Two Stud Corner with Metal Drywall Backup Clips
In order to provide on-going maintenance of Approach SO common areas and to ensure easement rights a homeowners association was formed complete with Articles of Incorporation and Declaration of Covenants Conditions and Restrictions
The 3S Approach SO units included 10 detached homes 7 duplexes 2 threeplexes and 2 fourplexes Units ranged in size from 704 square feet to 1 116 square feet One unit a detached split level contained 1 OOS square feet of finished living space and 392 square feet of expandable space in the lower level
Although the objective of Approach SO was to demonstrate low-cost marshyketable land development and construction techniques some of the demonshystrated systems were not necessarily the least costly way to build in Las Vegas For example Las Vegas has been traditionally a slab-on-grade town with very few crawl space and basement homes built in recent years The Approach SO committee decided however to build basement and crawl space homes to show alternatives in foundation and floor construction Conshystruction techniques and systems demonstrated included the following
Modular Design-Units were designed to a module of 2 feet out-to-out to reduce scrap waste and labor They were also designed to minimize length of walls and partitions
Value Engineering Techniques bull Trusses walls and floor joists were framed 24 inches on-center in line
with each other bull Two-stud corners were used with metal drywall backup clips bull Plywood box beam headers were used instead of solid wood headers
These headers created a cavity for insulation bull Windows 22112 inches wide were placed between studs 24 inches on
center to eliminate window headers bull In-line off-center spliced joists were used on one home This system
allowed use of smaller floor joists and reduced labor costs bull Single top plates were used on all walls bull Metal drywall backup clips eliminated studs as drywall nailers bull Single layer glue-nailed TampG plywood (Sturdi-floor) systems reduced
material and labor and contributed to a stiffer floor with fewer squeeks bull Single layer plywood siding eliminated sheathing and corner bracing bull Bulkheads (furred-down soffits) were eliminated over kitchen cabinets bull Amount of blocking and bracing was reduced bull Partition posts (channels) were eliminated
Construction Systems bull Reduced thickness and width of footing based on soil bearing tests bull A 2112 inch thick slab used in three slabs as demonstration bull Pressure treated wood foundations used in one crawl space and one
basement to demonstrate an alternative to cast-in-place concrete and conshycrete block foundations
bull Underfloor plenum heatingcooling system used in two homes System uses underfloor area as supply plenum eliminating ducts
bull Waterproof basement techniques demonstrated in basement homes bull Prefabricated DWV plumbing trees bull Polybutylene hot and cold water supply plumbing was demonstrated in
three homes
11
Triple Window Opening in Bearing Wall
single 2X4 op plate -+1_-
no headers
ead bloc
22 12 in~~~==tt==~----Hr--openings 1
2x4 24 in oc
II blocks -+1-
Open Soffit Overhang
-~ -t~1
-
22V2-lnch Wide Windows Between 24-lnch On-Center Studs Plywood Box Beam Headers
12
ps
f-shy
I shy
n
x r No Bulkhead Over Cabinets
Interior PartitionExterior Wall Connection
t
ISingle Layer Plywood Siding 34-lnch Tongue and Groove Single Layer APA Sturd-I-Floor
13
Exterior Wall 24 Inches On Center Single Top Plate
1== Single pp plate ~ I
[ jg fo (7~
=
l =
24-lnch On-Center In-Line Framing In-Line Off-Center Spliced Floor Joists
5
In-Line Off-Center Spliced Floor Joists
14
Light Gauge Steel Studs
shyPressure-Treated Wood Foundation
bull Light gauge steel studs were installed in one demonstration unit to show an alternative to wood interior partition framing
In most cases the systems demonstrated proved to be less costly than conventional techniques and systems In some cases the demonstrated system mayor may not be cost effective in some locales depending on local variations in material and labor costs
A house-by-house description of the demonstration units follows Seven of the units contained many of the systems that were being shown as techniques that might be usable in areas other than Las Vegas such as basements crawl spaces wood floor framing methods All 38 units contained value engineered framing sheathing Siding and other cost-reduction systems
Prefabricated Plastic DWV Plumbing Tree Polybutylene Water Supply Plumbing
15
- -
Plan 1-A one-story 782-square-foot twoshybedroom one-bath home featuring engineered framshying underfloor plenum heatingcooling pressure treated wood foundation steel interior partitions and polybutylene supply plumbing
-~ 7
bedoom -j 1---_--ir
-bedroom
garage
-shy
bHroom great room
garage
Plan 1 shy AllemIe ~middot~~_
An alternate version of Plan 1 was built to evaluate the value of certain architectural features in a small home Plan 1 contained an inset deck which provided a somewhat private outdoor space within the floor plan of the home The alternate version was designed without the inset and with the kitchen made 2 feet wider which added about 62 square feet of living area These changes will be evaluated as to marketability of the two units
16
Plan 2-A one-story 1040-square-foot three-bedroom two-bath home with value engineered framing and an underfloor plenum heatingcooling system
drooml Plan 3-A two-story 11 04-square-foot three-bedroom 1112 bath home
featuring waterproof basement construction and a lower-priced redwood lap concrete
siding
bedroom
dtnlng
conclII ptlO
living
patio bull
dining
garage
Plan 3
17
~-~ Plan 4-This plan was built as a split level and also as a slab-on-grade home The
split level version featured engineered framing in-line off center spliced floor joists pressure treated wood foundation and polybutylene supply plumbing It contained 1008 square feet of finished floor area with 392 square feet of expandable area in the lower level Rough-in for a second full bath was provided in the lower level
~~J
-~~
bbullbull oom edoomt --l l
F7 [- ~
-uplusmn~Ll n garage
The slab version of plan 4 contained 1008 square feet of living area two bedrooms and one bath It featured value engineered framing and polybutylene supply plumbing
18
Duplex-Each of the four floor plans was repeated in a duplex vershysion at least once within the subdivishysion The duplexes were basically the same with the obvious exception of firewalls included between units
UpperL
~hh _____ bull OL-
Threeplex
Triplex
11
Threeplex Under ConstructionshyThe threeplex buildings contained two two-story units and one one-story unit
19
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
I
Typical Trench Detail
Approach 80 Under Construction
The road system within the 42 acres was designed to provide adequate movement for both vehicles and emergency equipment while minimizing high speed through traffic The goal was to provide each lot and common area with satisfactory access while limiting excessive pavement and right-ot-way to save land and development costs as well as reduce tuture maintenance costs Dead end streets were utilized where cul-de-sacs would normally be required saving land and paving costs Turnaround easements were provided
Jim Cashman a Riverside California builder and chairman ot the NAHB Land Use Committee assisted in negotiating approvals of the land plan Many of the deviations from Las Vegas standards were approved by the city while compromises were made on other requests Table 1 shows the usual Las Vegas land development requirements the deviations requested and the final approved designs
In addition longer than normal 4-inch house connection sewer service was allowed across public streets to main sewer lines located in easements The 20-inch minimum easement required tor 4-inch water lines was reduced to 18 inches More than one group ot townhouses were served by a single 2-inch domestic water meter where an individual meter is normally required for each unit Four-inch water mains were allowed in streets other than cul-de-sacs
The major perimeter streets required street lights conforming to the Las Vegas standards However the street lights installed in the interior of the
9
Table 1 Approach 80 Land Plan Negotiations with the City of Las Vegas
Item
R-1 lot size
Front yard set back
Side yard
Street right-of-way
Street paving
Dead end streets
Subdivision wall
Sidewalks
Sewer
Standard
60 x 120
25
0 10
60
41
Cul-de-sac
Concrete block
5 each side
8 mainline
Requested
40 x 80 45 X 75
15
0
10 5 garage
20 side 30 interior 34 entry
16 side 20 interior 24 entry
Tee section
Open sections and fencing
4 one side
4 amp6 main
Approved
40 X 90 45 X 80
15
0 10
5 garage
20 36 44
16 28 36
Break away barrier
Open sections and fencing
4 one side
4 amp6 main
)
---- --shy
Sewer and Water Plan UNO f I [ L 0 [ 0
== Z=--==
r----- ----- 7 bull a bull a -----------shy---~0--- 0 bull 1~
--- shy
( I I
I I
I
---+----+--
I
~ I I -
~ i I I i
o
- ~ 0
10
subdivision were the down type Ughting based on foot candle measure of lighting rather than maximum distance between lights
Homeowners
The Houses
I I
~i rf
Two Stud Corner with Metal Drywall Backup Clips
In order to provide on-going maintenance of Approach SO common areas and to ensure easement rights a homeowners association was formed complete with Articles of Incorporation and Declaration of Covenants Conditions and Restrictions
The 3S Approach SO units included 10 detached homes 7 duplexes 2 threeplexes and 2 fourplexes Units ranged in size from 704 square feet to 1 116 square feet One unit a detached split level contained 1 OOS square feet of finished living space and 392 square feet of expandable space in the lower level
Although the objective of Approach SO was to demonstrate low-cost marshyketable land development and construction techniques some of the demonshystrated systems were not necessarily the least costly way to build in Las Vegas For example Las Vegas has been traditionally a slab-on-grade town with very few crawl space and basement homes built in recent years The Approach SO committee decided however to build basement and crawl space homes to show alternatives in foundation and floor construction Conshystruction techniques and systems demonstrated included the following
Modular Design-Units were designed to a module of 2 feet out-to-out to reduce scrap waste and labor They were also designed to minimize length of walls and partitions
Value Engineering Techniques bull Trusses walls and floor joists were framed 24 inches on-center in line
with each other bull Two-stud corners were used with metal drywall backup clips bull Plywood box beam headers were used instead of solid wood headers
These headers created a cavity for insulation bull Windows 22112 inches wide were placed between studs 24 inches on
center to eliminate window headers bull In-line off-center spliced joists were used on one home This system
allowed use of smaller floor joists and reduced labor costs bull Single top plates were used on all walls bull Metal drywall backup clips eliminated studs as drywall nailers bull Single layer glue-nailed TampG plywood (Sturdi-floor) systems reduced
material and labor and contributed to a stiffer floor with fewer squeeks bull Single layer plywood siding eliminated sheathing and corner bracing bull Bulkheads (furred-down soffits) were eliminated over kitchen cabinets bull Amount of blocking and bracing was reduced bull Partition posts (channels) were eliminated
Construction Systems bull Reduced thickness and width of footing based on soil bearing tests bull A 2112 inch thick slab used in three slabs as demonstration bull Pressure treated wood foundations used in one crawl space and one
basement to demonstrate an alternative to cast-in-place concrete and conshycrete block foundations
bull Underfloor plenum heatingcooling system used in two homes System uses underfloor area as supply plenum eliminating ducts
bull Waterproof basement techniques demonstrated in basement homes bull Prefabricated DWV plumbing trees bull Polybutylene hot and cold water supply plumbing was demonstrated in
three homes
11
Triple Window Opening in Bearing Wall
single 2X4 op plate -+1_-
no headers
ead bloc
22 12 in~~~==tt==~----Hr--openings 1
2x4 24 in oc
II blocks -+1-
Open Soffit Overhang
-~ -t~1
-
22V2-lnch Wide Windows Between 24-lnch On-Center Studs Plywood Box Beam Headers
12
ps
f-shy
I shy
n
x r No Bulkhead Over Cabinets
Interior PartitionExterior Wall Connection
t
ISingle Layer Plywood Siding 34-lnch Tongue and Groove Single Layer APA Sturd-I-Floor
13
Exterior Wall 24 Inches On Center Single Top Plate
1== Single pp plate ~ I
[ jg fo (7~
=
l =
24-lnch On-Center In-Line Framing In-Line Off-Center Spliced Floor Joists
5
In-Line Off-Center Spliced Floor Joists
14
Light Gauge Steel Studs
shyPressure-Treated Wood Foundation
bull Light gauge steel studs were installed in one demonstration unit to show an alternative to wood interior partition framing
In most cases the systems demonstrated proved to be less costly than conventional techniques and systems In some cases the demonstrated system mayor may not be cost effective in some locales depending on local variations in material and labor costs
A house-by-house description of the demonstration units follows Seven of the units contained many of the systems that were being shown as techniques that might be usable in areas other than Las Vegas such as basements crawl spaces wood floor framing methods All 38 units contained value engineered framing sheathing Siding and other cost-reduction systems
Prefabricated Plastic DWV Plumbing Tree Polybutylene Water Supply Plumbing
15
- -
Plan 1-A one-story 782-square-foot twoshybedroom one-bath home featuring engineered framshying underfloor plenum heatingcooling pressure treated wood foundation steel interior partitions and polybutylene supply plumbing
-~ 7
bedoom -j 1---_--ir
-bedroom
garage
-shy
bHroom great room
garage
Plan 1 shy AllemIe ~middot~~_
An alternate version of Plan 1 was built to evaluate the value of certain architectural features in a small home Plan 1 contained an inset deck which provided a somewhat private outdoor space within the floor plan of the home The alternate version was designed without the inset and with the kitchen made 2 feet wider which added about 62 square feet of living area These changes will be evaluated as to marketability of the two units
16
Plan 2-A one-story 1040-square-foot three-bedroom two-bath home with value engineered framing and an underfloor plenum heatingcooling system
drooml Plan 3-A two-story 11 04-square-foot three-bedroom 1112 bath home
featuring waterproof basement construction and a lower-priced redwood lap concrete
siding
bedroom
dtnlng
conclII ptlO
living
patio bull
dining
garage
Plan 3
17
~-~ Plan 4-This plan was built as a split level and also as a slab-on-grade home The
split level version featured engineered framing in-line off center spliced floor joists pressure treated wood foundation and polybutylene supply plumbing It contained 1008 square feet of finished floor area with 392 square feet of expandable area in the lower level Rough-in for a second full bath was provided in the lower level
~~J
-~~
bbullbull oom edoomt --l l
F7 [- ~
-uplusmn~Ll n garage
The slab version of plan 4 contained 1008 square feet of living area two bedrooms and one bath It featured value engineered framing and polybutylene supply plumbing
18
Duplex-Each of the four floor plans was repeated in a duplex vershysion at least once within the subdivishysion The duplexes were basically the same with the obvious exception of firewalls included between units
UpperL
~hh _____ bull OL-
Threeplex
Triplex
11
Threeplex Under ConstructionshyThe threeplex buildings contained two two-story units and one one-story unit
19
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Table 1 Approach 80 Land Plan Negotiations with the City of Las Vegas
Item
R-1 lot size
Front yard set back
Side yard
Street right-of-way
Street paving
Dead end streets
Subdivision wall
Sidewalks
Sewer
Standard
60 x 120
25
0 10
60
41
Cul-de-sac
Concrete block
5 each side
8 mainline
Requested
40 x 80 45 X 75
15
0
10 5 garage
20 side 30 interior 34 entry
16 side 20 interior 24 entry
Tee section
Open sections and fencing
4 one side
4 amp6 main
Approved
40 X 90 45 X 80
15
0 10
5 garage
20 36 44
16 28 36
Break away barrier
Open sections and fencing
4 one side
4 amp6 main
)
---- --shy
Sewer and Water Plan UNO f I [ L 0 [ 0
== Z=--==
r----- ----- 7 bull a bull a -----------shy---~0--- 0 bull 1~
--- shy
( I I
I I
I
---+----+--
I
~ I I -
~ i I I i
o
- ~ 0
10
subdivision were the down type Ughting based on foot candle measure of lighting rather than maximum distance between lights
Homeowners
The Houses
I I
~i rf
Two Stud Corner with Metal Drywall Backup Clips
In order to provide on-going maintenance of Approach SO common areas and to ensure easement rights a homeowners association was formed complete with Articles of Incorporation and Declaration of Covenants Conditions and Restrictions
The 3S Approach SO units included 10 detached homes 7 duplexes 2 threeplexes and 2 fourplexes Units ranged in size from 704 square feet to 1 116 square feet One unit a detached split level contained 1 OOS square feet of finished living space and 392 square feet of expandable space in the lower level
Although the objective of Approach SO was to demonstrate low-cost marshyketable land development and construction techniques some of the demonshystrated systems were not necessarily the least costly way to build in Las Vegas For example Las Vegas has been traditionally a slab-on-grade town with very few crawl space and basement homes built in recent years The Approach SO committee decided however to build basement and crawl space homes to show alternatives in foundation and floor construction Conshystruction techniques and systems demonstrated included the following
Modular Design-Units were designed to a module of 2 feet out-to-out to reduce scrap waste and labor They were also designed to minimize length of walls and partitions
Value Engineering Techniques bull Trusses walls and floor joists were framed 24 inches on-center in line
with each other bull Two-stud corners were used with metal drywall backup clips bull Plywood box beam headers were used instead of solid wood headers
These headers created a cavity for insulation bull Windows 22112 inches wide were placed between studs 24 inches on
center to eliminate window headers bull In-line off-center spliced joists were used on one home This system
allowed use of smaller floor joists and reduced labor costs bull Single top plates were used on all walls bull Metal drywall backup clips eliminated studs as drywall nailers bull Single layer glue-nailed TampG plywood (Sturdi-floor) systems reduced
material and labor and contributed to a stiffer floor with fewer squeeks bull Single layer plywood siding eliminated sheathing and corner bracing bull Bulkheads (furred-down soffits) were eliminated over kitchen cabinets bull Amount of blocking and bracing was reduced bull Partition posts (channels) were eliminated
Construction Systems bull Reduced thickness and width of footing based on soil bearing tests bull A 2112 inch thick slab used in three slabs as demonstration bull Pressure treated wood foundations used in one crawl space and one
basement to demonstrate an alternative to cast-in-place concrete and conshycrete block foundations
bull Underfloor plenum heatingcooling system used in two homes System uses underfloor area as supply plenum eliminating ducts
bull Waterproof basement techniques demonstrated in basement homes bull Prefabricated DWV plumbing trees bull Polybutylene hot and cold water supply plumbing was demonstrated in
three homes
11
Triple Window Opening in Bearing Wall
single 2X4 op plate -+1_-
no headers
ead bloc
22 12 in~~~==tt==~----Hr--openings 1
2x4 24 in oc
II blocks -+1-
Open Soffit Overhang
-~ -t~1
-
22V2-lnch Wide Windows Between 24-lnch On-Center Studs Plywood Box Beam Headers
12
ps
f-shy
I shy
n
x r No Bulkhead Over Cabinets
Interior PartitionExterior Wall Connection
t
ISingle Layer Plywood Siding 34-lnch Tongue and Groove Single Layer APA Sturd-I-Floor
13
Exterior Wall 24 Inches On Center Single Top Plate
1== Single pp plate ~ I
[ jg fo (7~
=
l =
24-lnch On-Center In-Line Framing In-Line Off-Center Spliced Floor Joists
5
In-Line Off-Center Spliced Floor Joists
14
Light Gauge Steel Studs
shyPressure-Treated Wood Foundation
bull Light gauge steel studs were installed in one demonstration unit to show an alternative to wood interior partition framing
In most cases the systems demonstrated proved to be less costly than conventional techniques and systems In some cases the demonstrated system mayor may not be cost effective in some locales depending on local variations in material and labor costs
A house-by-house description of the demonstration units follows Seven of the units contained many of the systems that were being shown as techniques that might be usable in areas other than Las Vegas such as basements crawl spaces wood floor framing methods All 38 units contained value engineered framing sheathing Siding and other cost-reduction systems
Prefabricated Plastic DWV Plumbing Tree Polybutylene Water Supply Plumbing
15
- -
Plan 1-A one-story 782-square-foot twoshybedroom one-bath home featuring engineered framshying underfloor plenum heatingcooling pressure treated wood foundation steel interior partitions and polybutylene supply plumbing
-~ 7
bedoom -j 1---_--ir
-bedroom
garage
-shy
bHroom great room
garage
Plan 1 shy AllemIe ~middot~~_
An alternate version of Plan 1 was built to evaluate the value of certain architectural features in a small home Plan 1 contained an inset deck which provided a somewhat private outdoor space within the floor plan of the home The alternate version was designed without the inset and with the kitchen made 2 feet wider which added about 62 square feet of living area These changes will be evaluated as to marketability of the two units
16
Plan 2-A one-story 1040-square-foot three-bedroom two-bath home with value engineered framing and an underfloor plenum heatingcooling system
drooml Plan 3-A two-story 11 04-square-foot three-bedroom 1112 bath home
featuring waterproof basement construction and a lower-priced redwood lap concrete
siding
bedroom
dtnlng
conclII ptlO
living
patio bull
dining
garage
Plan 3
17
~-~ Plan 4-This plan was built as a split level and also as a slab-on-grade home The
split level version featured engineered framing in-line off center spliced floor joists pressure treated wood foundation and polybutylene supply plumbing It contained 1008 square feet of finished floor area with 392 square feet of expandable area in the lower level Rough-in for a second full bath was provided in the lower level
~~J
-~~
bbullbull oom edoomt --l l
F7 [- ~
-uplusmn~Ll n garage
The slab version of plan 4 contained 1008 square feet of living area two bedrooms and one bath It featured value engineered framing and polybutylene supply plumbing
18
Duplex-Each of the four floor plans was repeated in a duplex vershysion at least once within the subdivishysion The duplexes were basically the same with the obvious exception of firewalls included between units
UpperL
~hh _____ bull OL-
Threeplex
Triplex
11
Threeplex Under ConstructionshyThe threeplex buildings contained two two-story units and one one-story unit
19
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
subdivision were the down type Ughting based on foot candle measure of lighting rather than maximum distance between lights
Homeowners
The Houses
I I
~i rf
Two Stud Corner with Metal Drywall Backup Clips
In order to provide on-going maintenance of Approach SO common areas and to ensure easement rights a homeowners association was formed complete with Articles of Incorporation and Declaration of Covenants Conditions and Restrictions
The 3S Approach SO units included 10 detached homes 7 duplexes 2 threeplexes and 2 fourplexes Units ranged in size from 704 square feet to 1 116 square feet One unit a detached split level contained 1 OOS square feet of finished living space and 392 square feet of expandable space in the lower level
Although the objective of Approach SO was to demonstrate low-cost marshyketable land development and construction techniques some of the demonshystrated systems were not necessarily the least costly way to build in Las Vegas For example Las Vegas has been traditionally a slab-on-grade town with very few crawl space and basement homes built in recent years The Approach SO committee decided however to build basement and crawl space homes to show alternatives in foundation and floor construction Conshystruction techniques and systems demonstrated included the following
Modular Design-Units were designed to a module of 2 feet out-to-out to reduce scrap waste and labor They were also designed to minimize length of walls and partitions
Value Engineering Techniques bull Trusses walls and floor joists were framed 24 inches on-center in line
with each other bull Two-stud corners were used with metal drywall backup clips bull Plywood box beam headers were used instead of solid wood headers
These headers created a cavity for insulation bull Windows 22112 inches wide were placed between studs 24 inches on
center to eliminate window headers bull In-line off-center spliced joists were used on one home This system
allowed use of smaller floor joists and reduced labor costs bull Single top plates were used on all walls bull Metal drywall backup clips eliminated studs as drywall nailers bull Single layer glue-nailed TampG plywood (Sturdi-floor) systems reduced
material and labor and contributed to a stiffer floor with fewer squeeks bull Single layer plywood siding eliminated sheathing and corner bracing bull Bulkheads (furred-down soffits) were eliminated over kitchen cabinets bull Amount of blocking and bracing was reduced bull Partition posts (channels) were eliminated
Construction Systems bull Reduced thickness and width of footing based on soil bearing tests bull A 2112 inch thick slab used in three slabs as demonstration bull Pressure treated wood foundations used in one crawl space and one
basement to demonstrate an alternative to cast-in-place concrete and conshycrete block foundations
bull Underfloor plenum heatingcooling system used in two homes System uses underfloor area as supply plenum eliminating ducts
bull Waterproof basement techniques demonstrated in basement homes bull Prefabricated DWV plumbing trees bull Polybutylene hot and cold water supply plumbing was demonstrated in
three homes
11
Triple Window Opening in Bearing Wall
single 2X4 op plate -+1_-
no headers
ead bloc
22 12 in~~~==tt==~----Hr--openings 1
2x4 24 in oc
II blocks -+1-
Open Soffit Overhang
-~ -t~1
-
22V2-lnch Wide Windows Between 24-lnch On-Center Studs Plywood Box Beam Headers
12
ps
f-shy
I shy
n
x r No Bulkhead Over Cabinets
Interior PartitionExterior Wall Connection
t
ISingle Layer Plywood Siding 34-lnch Tongue and Groove Single Layer APA Sturd-I-Floor
13
Exterior Wall 24 Inches On Center Single Top Plate
1== Single pp plate ~ I
[ jg fo (7~
=
l =
24-lnch On-Center In-Line Framing In-Line Off-Center Spliced Floor Joists
5
In-Line Off-Center Spliced Floor Joists
14
Light Gauge Steel Studs
shyPressure-Treated Wood Foundation
bull Light gauge steel studs were installed in one demonstration unit to show an alternative to wood interior partition framing
In most cases the systems demonstrated proved to be less costly than conventional techniques and systems In some cases the demonstrated system mayor may not be cost effective in some locales depending on local variations in material and labor costs
A house-by-house description of the demonstration units follows Seven of the units contained many of the systems that were being shown as techniques that might be usable in areas other than Las Vegas such as basements crawl spaces wood floor framing methods All 38 units contained value engineered framing sheathing Siding and other cost-reduction systems
Prefabricated Plastic DWV Plumbing Tree Polybutylene Water Supply Plumbing
15
- -
Plan 1-A one-story 782-square-foot twoshybedroom one-bath home featuring engineered framshying underfloor plenum heatingcooling pressure treated wood foundation steel interior partitions and polybutylene supply plumbing
-~ 7
bedoom -j 1---_--ir
-bedroom
garage
-shy
bHroom great room
garage
Plan 1 shy AllemIe ~middot~~_
An alternate version of Plan 1 was built to evaluate the value of certain architectural features in a small home Plan 1 contained an inset deck which provided a somewhat private outdoor space within the floor plan of the home The alternate version was designed without the inset and with the kitchen made 2 feet wider which added about 62 square feet of living area These changes will be evaluated as to marketability of the two units
16
Plan 2-A one-story 1040-square-foot three-bedroom two-bath home with value engineered framing and an underfloor plenum heatingcooling system
drooml Plan 3-A two-story 11 04-square-foot three-bedroom 1112 bath home
featuring waterproof basement construction and a lower-priced redwood lap concrete
siding
bedroom
dtnlng
conclII ptlO
living
patio bull
dining
garage
Plan 3
17
~-~ Plan 4-This plan was built as a split level and also as a slab-on-grade home The
split level version featured engineered framing in-line off center spliced floor joists pressure treated wood foundation and polybutylene supply plumbing It contained 1008 square feet of finished floor area with 392 square feet of expandable area in the lower level Rough-in for a second full bath was provided in the lower level
~~J
-~~
bbullbull oom edoomt --l l
F7 [- ~
-uplusmn~Ll n garage
The slab version of plan 4 contained 1008 square feet of living area two bedrooms and one bath It featured value engineered framing and polybutylene supply plumbing
18
Duplex-Each of the four floor plans was repeated in a duplex vershysion at least once within the subdivishysion The duplexes were basically the same with the obvious exception of firewalls included between units
UpperL
~hh _____ bull OL-
Threeplex
Triplex
11
Threeplex Under ConstructionshyThe threeplex buildings contained two two-story units and one one-story unit
19
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Triple Window Opening in Bearing Wall
single 2X4 op plate -+1_-
no headers
ead bloc
22 12 in~~~==tt==~----Hr--openings 1
2x4 24 in oc
II blocks -+1-
Open Soffit Overhang
-~ -t~1
-
22V2-lnch Wide Windows Between 24-lnch On-Center Studs Plywood Box Beam Headers
12
ps
f-shy
I shy
n
x r No Bulkhead Over Cabinets
Interior PartitionExterior Wall Connection
t
ISingle Layer Plywood Siding 34-lnch Tongue and Groove Single Layer APA Sturd-I-Floor
13
Exterior Wall 24 Inches On Center Single Top Plate
1== Single pp plate ~ I
[ jg fo (7~
=
l =
24-lnch On-Center In-Line Framing In-Line Off-Center Spliced Floor Joists
5
In-Line Off-Center Spliced Floor Joists
14
Light Gauge Steel Studs
shyPressure-Treated Wood Foundation
bull Light gauge steel studs were installed in one demonstration unit to show an alternative to wood interior partition framing
In most cases the systems demonstrated proved to be less costly than conventional techniques and systems In some cases the demonstrated system mayor may not be cost effective in some locales depending on local variations in material and labor costs
A house-by-house description of the demonstration units follows Seven of the units contained many of the systems that were being shown as techniques that might be usable in areas other than Las Vegas such as basements crawl spaces wood floor framing methods All 38 units contained value engineered framing sheathing Siding and other cost-reduction systems
Prefabricated Plastic DWV Plumbing Tree Polybutylene Water Supply Plumbing
15
- -
Plan 1-A one-story 782-square-foot twoshybedroom one-bath home featuring engineered framshying underfloor plenum heatingcooling pressure treated wood foundation steel interior partitions and polybutylene supply plumbing
-~ 7
bedoom -j 1---_--ir
-bedroom
garage
-shy
bHroom great room
garage
Plan 1 shy AllemIe ~middot~~_
An alternate version of Plan 1 was built to evaluate the value of certain architectural features in a small home Plan 1 contained an inset deck which provided a somewhat private outdoor space within the floor plan of the home The alternate version was designed without the inset and with the kitchen made 2 feet wider which added about 62 square feet of living area These changes will be evaluated as to marketability of the two units
16
Plan 2-A one-story 1040-square-foot three-bedroom two-bath home with value engineered framing and an underfloor plenum heatingcooling system
drooml Plan 3-A two-story 11 04-square-foot three-bedroom 1112 bath home
featuring waterproof basement construction and a lower-priced redwood lap concrete
siding
bedroom
dtnlng
conclII ptlO
living
patio bull
dining
garage
Plan 3
17
~-~ Plan 4-This plan was built as a split level and also as a slab-on-grade home The
split level version featured engineered framing in-line off center spliced floor joists pressure treated wood foundation and polybutylene supply plumbing It contained 1008 square feet of finished floor area with 392 square feet of expandable area in the lower level Rough-in for a second full bath was provided in the lower level
~~J
-~~
bbullbull oom edoomt --l l
F7 [- ~
-uplusmn~Ll n garage
The slab version of plan 4 contained 1008 square feet of living area two bedrooms and one bath It featured value engineered framing and polybutylene supply plumbing
18
Duplex-Each of the four floor plans was repeated in a duplex vershysion at least once within the subdivishysion The duplexes were basically the same with the obvious exception of firewalls included between units
UpperL
~hh _____ bull OL-
Threeplex
Triplex
11
Threeplex Under ConstructionshyThe threeplex buildings contained two two-story units and one one-story unit
19
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
ps
f-shy
I shy
n
x r No Bulkhead Over Cabinets
Interior PartitionExterior Wall Connection
t
ISingle Layer Plywood Siding 34-lnch Tongue and Groove Single Layer APA Sturd-I-Floor
13
Exterior Wall 24 Inches On Center Single Top Plate
1== Single pp plate ~ I
[ jg fo (7~
=
l =
24-lnch On-Center In-Line Framing In-Line Off-Center Spliced Floor Joists
5
In-Line Off-Center Spliced Floor Joists
14
Light Gauge Steel Studs
shyPressure-Treated Wood Foundation
bull Light gauge steel studs were installed in one demonstration unit to show an alternative to wood interior partition framing
In most cases the systems demonstrated proved to be less costly than conventional techniques and systems In some cases the demonstrated system mayor may not be cost effective in some locales depending on local variations in material and labor costs
A house-by-house description of the demonstration units follows Seven of the units contained many of the systems that were being shown as techniques that might be usable in areas other than Las Vegas such as basements crawl spaces wood floor framing methods All 38 units contained value engineered framing sheathing Siding and other cost-reduction systems
Prefabricated Plastic DWV Plumbing Tree Polybutylene Water Supply Plumbing
15
- -
Plan 1-A one-story 782-square-foot twoshybedroom one-bath home featuring engineered framshying underfloor plenum heatingcooling pressure treated wood foundation steel interior partitions and polybutylene supply plumbing
-~ 7
bedoom -j 1---_--ir
-bedroom
garage
-shy
bHroom great room
garage
Plan 1 shy AllemIe ~middot~~_
An alternate version of Plan 1 was built to evaluate the value of certain architectural features in a small home Plan 1 contained an inset deck which provided a somewhat private outdoor space within the floor plan of the home The alternate version was designed without the inset and with the kitchen made 2 feet wider which added about 62 square feet of living area These changes will be evaluated as to marketability of the two units
16
Plan 2-A one-story 1040-square-foot three-bedroom two-bath home with value engineered framing and an underfloor plenum heatingcooling system
drooml Plan 3-A two-story 11 04-square-foot three-bedroom 1112 bath home
featuring waterproof basement construction and a lower-priced redwood lap concrete
siding
bedroom
dtnlng
conclII ptlO
living
patio bull
dining
garage
Plan 3
17
~-~ Plan 4-This plan was built as a split level and also as a slab-on-grade home The
split level version featured engineered framing in-line off center spliced floor joists pressure treated wood foundation and polybutylene supply plumbing It contained 1008 square feet of finished floor area with 392 square feet of expandable area in the lower level Rough-in for a second full bath was provided in the lower level
~~J
-~~
bbullbull oom edoomt --l l
F7 [- ~
-uplusmn~Ll n garage
The slab version of plan 4 contained 1008 square feet of living area two bedrooms and one bath It featured value engineered framing and polybutylene supply plumbing
18
Duplex-Each of the four floor plans was repeated in a duplex vershysion at least once within the subdivishysion The duplexes were basically the same with the obvious exception of firewalls included between units
UpperL
~hh _____ bull OL-
Threeplex
Triplex
11
Threeplex Under ConstructionshyThe threeplex buildings contained two two-story units and one one-story unit
19
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Exterior Wall 24 Inches On Center Single Top Plate
1== Single pp plate ~ I
[ jg fo (7~
=
l =
24-lnch On-Center In-Line Framing In-Line Off-Center Spliced Floor Joists
5
In-Line Off-Center Spliced Floor Joists
14
Light Gauge Steel Studs
shyPressure-Treated Wood Foundation
bull Light gauge steel studs were installed in one demonstration unit to show an alternative to wood interior partition framing
In most cases the systems demonstrated proved to be less costly than conventional techniques and systems In some cases the demonstrated system mayor may not be cost effective in some locales depending on local variations in material and labor costs
A house-by-house description of the demonstration units follows Seven of the units contained many of the systems that were being shown as techniques that might be usable in areas other than Las Vegas such as basements crawl spaces wood floor framing methods All 38 units contained value engineered framing sheathing Siding and other cost-reduction systems
Prefabricated Plastic DWV Plumbing Tree Polybutylene Water Supply Plumbing
15
- -
Plan 1-A one-story 782-square-foot twoshybedroom one-bath home featuring engineered framshying underfloor plenum heatingcooling pressure treated wood foundation steel interior partitions and polybutylene supply plumbing
-~ 7
bedoom -j 1---_--ir
-bedroom
garage
-shy
bHroom great room
garage
Plan 1 shy AllemIe ~middot~~_
An alternate version of Plan 1 was built to evaluate the value of certain architectural features in a small home Plan 1 contained an inset deck which provided a somewhat private outdoor space within the floor plan of the home The alternate version was designed without the inset and with the kitchen made 2 feet wider which added about 62 square feet of living area These changes will be evaluated as to marketability of the two units
16
Plan 2-A one-story 1040-square-foot three-bedroom two-bath home with value engineered framing and an underfloor plenum heatingcooling system
drooml Plan 3-A two-story 11 04-square-foot three-bedroom 1112 bath home
featuring waterproof basement construction and a lower-priced redwood lap concrete
siding
bedroom
dtnlng
conclII ptlO
living
patio bull
dining
garage
Plan 3
17
~-~ Plan 4-This plan was built as a split level and also as a slab-on-grade home The
split level version featured engineered framing in-line off center spliced floor joists pressure treated wood foundation and polybutylene supply plumbing It contained 1008 square feet of finished floor area with 392 square feet of expandable area in the lower level Rough-in for a second full bath was provided in the lower level
~~J
-~~
bbullbull oom edoomt --l l
F7 [- ~
-uplusmn~Ll n garage
The slab version of plan 4 contained 1008 square feet of living area two bedrooms and one bath It featured value engineered framing and polybutylene supply plumbing
18
Duplex-Each of the four floor plans was repeated in a duplex vershysion at least once within the subdivishysion The duplexes were basically the same with the obvious exception of firewalls included between units
UpperL
~hh _____ bull OL-
Threeplex
Triplex
11
Threeplex Under ConstructionshyThe threeplex buildings contained two two-story units and one one-story unit
19
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Light Gauge Steel Studs
shyPressure-Treated Wood Foundation
bull Light gauge steel studs were installed in one demonstration unit to show an alternative to wood interior partition framing
In most cases the systems demonstrated proved to be less costly than conventional techniques and systems In some cases the demonstrated system mayor may not be cost effective in some locales depending on local variations in material and labor costs
A house-by-house description of the demonstration units follows Seven of the units contained many of the systems that were being shown as techniques that might be usable in areas other than Las Vegas such as basements crawl spaces wood floor framing methods All 38 units contained value engineered framing sheathing Siding and other cost-reduction systems
Prefabricated Plastic DWV Plumbing Tree Polybutylene Water Supply Plumbing
15
- -
Plan 1-A one-story 782-square-foot twoshybedroom one-bath home featuring engineered framshying underfloor plenum heatingcooling pressure treated wood foundation steel interior partitions and polybutylene supply plumbing
-~ 7
bedoom -j 1---_--ir
-bedroom
garage
-shy
bHroom great room
garage
Plan 1 shy AllemIe ~middot~~_
An alternate version of Plan 1 was built to evaluate the value of certain architectural features in a small home Plan 1 contained an inset deck which provided a somewhat private outdoor space within the floor plan of the home The alternate version was designed without the inset and with the kitchen made 2 feet wider which added about 62 square feet of living area These changes will be evaluated as to marketability of the two units
16
Plan 2-A one-story 1040-square-foot three-bedroom two-bath home with value engineered framing and an underfloor plenum heatingcooling system
drooml Plan 3-A two-story 11 04-square-foot three-bedroom 1112 bath home
featuring waterproof basement construction and a lower-priced redwood lap concrete
siding
bedroom
dtnlng
conclII ptlO
living
patio bull
dining
garage
Plan 3
17
~-~ Plan 4-This plan was built as a split level and also as a slab-on-grade home The
split level version featured engineered framing in-line off center spliced floor joists pressure treated wood foundation and polybutylene supply plumbing It contained 1008 square feet of finished floor area with 392 square feet of expandable area in the lower level Rough-in for a second full bath was provided in the lower level
~~J
-~~
bbullbull oom edoomt --l l
F7 [- ~
-uplusmn~Ll n garage
The slab version of plan 4 contained 1008 square feet of living area two bedrooms and one bath It featured value engineered framing and polybutylene supply plumbing
18
Duplex-Each of the four floor plans was repeated in a duplex vershysion at least once within the subdivishysion The duplexes were basically the same with the obvious exception of firewalls included between units
UpperL
~hh _____ bull OL-
Threeplex
Triplex
11
Threeplex Under ConstructionshyThe threeplex buildings contained two two-story units and one one-story unit
19
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
- -
Plan 1-A one-story 782-square-foot twoshybedroom one-bath home featuring engineered framshying underfloor plenum heatingcooling pressure treated wood foundation steel interior partitions and polybutylene supply plumbing
-~ 7
bedoom -j 1---_--ir
-bedroom
garage
-shy
bHroom great room
garage
Plan 1 shy AllemIe ~middot~~_
An alternate version of Plan 1 was built to evaluate the value of certain architectural features in a small home Plan 1 contained an inset deck which provided a somewhat private outdoor space within the floor plan of the home The alternate version was designed without the inset and with the kitchen made 2 feet wider which added about 62 square feet of living area These changes will be evaluated as to marketability of the two units
16
Plan 2-A one-story 1040-square-foot three-bedroom two-bath home with value engineered framing and an underfloor plenum heatingcooling system
drooml Plan 3-A two-story 11 04-square-foot three-bedroom 1112 bath home
featuring waterproof basement construction and a lower-priced redwood lap concrete
siding
bedroom
dtnlng
conclII ptlO
living
patio bull
dining
garage
Plan 3
17
~-~ Plan 4-This plan was built as a split level and also as a slab-on-grade home The
split level version featured engineered framing in-line off center spliced floor joists pressure treated wood foundation and polybutylene supply plumbing It contained 1008 square feet of finished floor area with 392 square feet of expandable area in the lower level Rough-in for a second full bath was provided in the lower level
~~J
-~~
bbullbull oom edoomt --l l
F7 [- ~
-uplusmn~Ll n garage
The slab version of plan 4 contained 1008 square feet of living area two bedrooms and one bath It featured value engineered framing and polybutylene supply plumbing
18
Duplex-Each of the four floor plans was repeated in a duplex vershysion at least once within the subdivishysion The duplexes were basically the same with the obvious exception of firewalls included between units
UpperL
~hh _____ bull OL-
Threeplex
Triplex
11
Threeplex Under ConstructionshyThe threeplex buildings contained two two-story units and one one-story unit
19
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Plan 2-A one-story 1040-square-foot three-bedroom two-bath home with value engineered framing and an underfloor plenum heatingcooling system
drooml Plan 3-A two-story 11 04-square-foot three-bedroom 1112 bath home
featuring waterproof basement construction and a lower-priced redwood lap concrete
siding
bedroom
dtnlng
conclII ptlO
living
patio bull
dining
garage
Plan 3
17
~-~ Plan 4-This plan was built as a split level and also as a slab-on-grade home The
split level version featured engineered framing in-line off center spliced floor joists pressure treated wood foundation and polybutylene supply plumbing It contained 1008 square feet of finished floor area with 392 square feet of expandable area in the lower level Rough-in for a second full bath was provided in the lower level
~~J
-~~
bbullbull oom edoomt --l l
F7 [- ~
-uplusmn~Ll n garage
The slab version of plan 4 contained 1008 square feet of living area two bedrooms and one bath It featured value engineered framing and polybutylene supply plumbing
18
Duplex-Each of the four floor plans was repeated in a duplex vershysion at least once within the subdivishysion The duplexes were basically the same with the obvious exception of firewalls included between units
UpperL
~hh _____ bull OL-
Threeplex
Triplex
11
Threeplex Under ConstructionshyThe threeplex buildings contained two two-story units and one one-story unit
19
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
~-~ Plan 4-This plan was built as a split level and also as a slab-on-grade home The
split level version featured engineered framing in-line off center spliced floor joists pressure treated wood foundation and polybutylene supply plumbing It contained 1008 square feet of finished floor area with 392 square feet of expandable area in the lower level Rough-in for a second full bath was provided in the lower level
~~J
-~~
bbullbull oom edoomt --l l
F7 [- ~
-uplusmn~Ll n garage
The slab version of plan 4 contained 1008 square feet of living area two bedrooms and one bath It featured value engineered framing and polybutylene supply plumbing
18
Duplex-Each of the four floor plans was repeated in a duplex vershysion at least once within the subdivishysion The duplexes were basically the same with the obvious exception of firewalls included between units
UpperL
~hh _____ bull OL-
Threeplex
Triplex
11
Threeplex Under ConstructionshyThe threeplex buildings contained two two-story units and one one-story unit
19
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Duplex-Each of the four floor plans was repeated in a duplex vershysion at least once within the subdivishysion The duplexes were basically the same with the obvious exception of firewalls included between units
UpperL
~hh _____ bull OL-
Threeplex
Triplex
11
Threeplex Under ConstructionshyThe threeplex buildings contained two two-story units and one one-story unit
19
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Fourplex-The fourplexes conshytained four one-story units Value enshygineered framing techniques were used throughout
Quadruplex
Fourplex
IH(jroom
In-Place Cost Analysis
Land Development
NAHB Research Foundation industrial engineers monitored all Approach 80 costs and compared them with conventional Las Vegas subdivision costs using local codes standards and building practices Building to existing Las Vegas land development standards would have made the project impossible to build as conceived inasmuch as the requirements for street widths sidewalks and minimum lot sizes (see table 1) would have reduced total yield from 38 units to 33 units This fact was considered when developing comparashytive in-place costs
Approach 80 land development costs consisted of both on site and offsite costs That is the City of Las Vegas required that the subdivision pay for development of two major thoroughfares that abut the site Costs of off-site utilities sidewalks curbs and gutters and street lighting were absorbed by Approach 80 Table 2 shows land development costs for the entire project and the amounts that were inside and outside of the subdivision Although some of the City standards were waived inside the project none were waived for offsite work
Table 2 shows that a large percentage (456) of all land development costs were expended offsite Because the offsite work was associated with public rights-of-way the city was unwilling to waive standards in most cases The one exception was a reduction in perimeter fence requirements Las Vegas stanshydards require a concrete block wall along major streets For Approach 80 a revised design that contained open sections and fencing rather than solid concrete block was allowed Total fencing costs were increased after the project began when the Approach 80 site was declared to be in a flood plain Therefore a 335-foot-long concrete block diverter fence was required along the western edge of the property
20
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Table 2 Approach 80 Land Development Costs-Onsite v Offsite Cost Comparisons
Cost Item On-Site Off-Site Total
Underground trench $1432980 $1301652 $2734632 Water system 1289188 323608 1612796 Sewer system 2150420 581970 2732390 House water and sewer 1823050 0 1823050 Exterior street paving 0 6413298 6413298 Interior street paving 1534440 0 1534440 Exterior sidewalk 0 1230288 1230288 Interior sidewalk 548986 0 548986 Exterior curb and gutter 0 974890 974890 Interior curb and gutter 686432 0 686432 Interior cross gutter 18582 0 18582 Interior concrete drainage 37392 0 37392 Interior 2 x 4 headers 407664 0 407664 Regrade interior streets 467514 0 467514 Regrade exterior streets 0 283594 283594 Fence 0 1797742 1797742 Street lighting 260000 910000 1170000 Barricades 120000 0 120000 Landscaping sprinklers 4210000 0 4210000 Civil engineering 2184848 546174 2731022
Totals $17171496 $14363216 $31534712 Average per unit $451881 $377979 $829860 Percent of total 544 456 1000
21
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Table 3 Approach 80 Land Development Cost Comparisons As-Built v Conventional Las Vegas Practice
As-Cost Item Built Conventional Savings
Underground trench Water system Sewer system House water and sewer Exterior street paving Interior street paving Exterior sidewalk Interior sidewalk Exterior curb and gutter Interior curb and gutter Interior cross gutter Interior concrete drainage Interior 2x4 headers Regrade interior streets Regrade exterior streets Fence Street lighting Barricades Landscaping sprinklers Civil engineering
$2734632 1612796 2732390 1823050 6413298 1534440 1230288 548986 974890 686432
18582 37392
407664 467514 283594
1797742 1170000
120000 4210000 2731022
$2734632 0 2037712 424916 3099204 366814 1823050 0 6413298 0 3672514 2138074 1230288 0 1360400 811414 974890 0
1264146 577714 18582 0 37392 0
407664 0 467514 0 283594 0
2390998 593256 1690000 520000
120000 0 4210000 0 2731022 0
Totals $31534712 $36966900 $5432188 Averageunit $829861 $1120209 $290348 Percent savings 259
$3153471238 unit subdivision = $829861 per unit $3696690033 unit subdivision = $1120209 per unit
Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have been possible instead of 38 as built
Table 3 shows the total land development costs of Approach 80 compared with probable costs if the subdivision were built conventionally to Las Vegas standards and practices The averages per unit reflect the fact that only 33 units could have been built if existing standards were used
Total subdivision cost reduction for land development was $5432188 These reductions resulted primarily from the following
Water system ($424916)-A 2-inch reduction in water main diameter throughout Eleven townhouses were serviced by a single 2-inch meter rather than by individual meters Three townhouses were serviced by a single 1-inch meter rather than by individual meters
Sewer system ($366814)-The standard 8-inch diameter main line was reduced to 4 and 6-inch mains throughout Four-inch house connections were allowed to cross under public streets to the main lines located in easements
Interior streets ($21 38074)-Standard rights-of-way were reduced from 60 feet for all streets to 20 feet for a side street 36 feet for interior streets and 44 feet for the entry street Paving width was reduced from 41 feet to 16 28 and 38 feet Pavement thickness was reduced from 3yen4-inch to 2-inch asphalt concrete
Interior Sidewalks ($811414)-Sidewalks were reduced from 5 feet wide on both sides to 4 feet wide on one side
22
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Direct Construction Costs
Interior curbs and gutters ($57n14)-Roll-type gutters were used inshystead of standard L type No curb and gutter on the narrow side street
Fence ($593256)-Solid masonry block wall replaced by partial block partial open space with fencing along major streets
Street lighting ($520000)-Seven standard Las Vegas street lights were replaced by three down-type lights within the interior of the subdivision
Actual direct construction costs were developed for each of the 38 units and then estimates were made to determine how much each unit would have cost if it had been built under Las Vegas codes and normal Las Vegas practices Cost savings were determined only on those items that were considered unique to Las Vegas construction methods In other words although a particular Apshyproach 80 system consisted of very efficient use of materials and labor it did not necessarily qualify as unique For example the electrical contractor was aSked to design the most efficient code-complying wiring system possible but since no innovative materials or techniques were used no cost reduction credit was taken for electrical wiring
Where deviations from normal practice or local codes were made material and labor take-offs resulted in cost-reduction estimates Table 4 shows actual direct construction costs versus the estimated costs that would have occurred had the same units been built conventionally
Total direct construction cost savings for Approach 80 amounted to $4696189 A discussion of the areas where costs were reduced follows
Rough Framing Sheathing Siding Carpentry Labor ($3665784)shyeVE framing techniques were used throughout the subdivision In 37 of the 38
Table 4 Approach 80 Direct Construction Cost Comparison As-Built Versus Conventional Las Vegas Codes and Practices
by Plan Number
Average Cost Per Unit Number Plan Number Built As-Built Conventional Savings
1 detached slab 1 $2252251 $2401707 $149456 1 detached crawl space 1 2465969 2680616 214647 1 alternate detached slab 1 2352375 2488310 135935 1 duplex slab garage 2 2186007 2313619 127612 1 duplex slab no garage 2 1857508 1964946 107438 2 detached crawl space 1 3006045 3239482 233437 2 duplex slab 4 2829029 2984575 155546 3 detached slab 3 3062906 3209023 146117 3 detached basement 1 3636430 3734765 98335 3 duplex slab 2 2774793 2896099 121306 4detached slab 1 2301369 2455248 153879 4 detached split level 1 3058114 3210121 152007 4 duplex slab garage 2 2323425 2458610 135185 4 duplex slab carport 2 2267313 2369089 128776 Threeplex end unit 4 2025503 2147933 122430 Threeplex middle unit 2 1602269 1681705 79436 Fourplex end unit 4 1713683 1789789 76106 Fourplex interior unit 4 1620327 1696404 76077
Totals 38 $87038069 $91734258 $4696189 Averageunit $2290476 $2414060 $123584 Percent savings 51
23
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Total Approach 80 Costs
homes interior partitions were framed with 2 x 4s spaced 24 inches on center The other unit contained light gage steel studs which are sometimes competitshyive with wood framing members Exterior walls were also framed 24 inches on center with the exception of the first story of the two-story units and the entire wall of the one two-story home with horizontal lap siding These exceptions were framed with 2 x 4s spaced 16 inches on center
No solid wood headers were used over openings Most were not needed inasmuch as windows were 2212 inches wide and fit between 24 inches-onshycenter studs Plywood box-beam headers were used over doors and sliding glass doors in load-bearing walls
Two stud corners were used throughout with metal drywall backup clips Partition posts or channels were not used Instead wherever a partition intersected with an exterior wall a midheight block was used to secure the partition and the metal drywall clips provided backing for gypsum wallboard Single top plates were used on exterior and interior walls
In homes with wood floors single-layer plywood sheathing (314 APA SturdshyI-Floor plywood) was used without separate underlayment and glued with BFG PL-400 structural adhesive In addition single-layer plywood siding without sheathing or building paper was used on 37 of the 38 units The exception was a two-story home with horizontal lapped redwood siding Building paper was installed before the siding was put on Average cost savings per unit was $96468
Foundations and Slabs ($517712)-No welded wire mesh was used in any of the Approach 80 slabs In addition footing widths and depths were reduced based upon soil-bearing tests In three of the units slab thickness was reduced from 312 inches to 212 inches to test the structural adequacy of a thinner residential slab Four-sack mix 2000-pound concrete was used throughout with the exception of the 212-inch slabs where more conventional five-sack mix was used Average cost savings amounted to $13624 per unit
Rough Plumbing ($48292)-Conventional copper supply pipe and plastic drain waste and vent pipe was used in all but three units In those three polybutylene pipe was used for all hot and cold supply piping Average savings forthe three PB homes was about$161 Had PB pipe been used in all 38 units total Approach 80 savings would have amounted to $6117
HeatingAir Conditioning ($52934)-Ductless underfloor heating cooling systems were installed in two units This Plenwood system reduced total HVAC costs by an average of $26467 because of the elimination of most supply ductwork
Roofing ($12n94)-Roofing felt was eliminated under asphalt shingles for an average cost reduction of $3363 per house Although required by Las Vegas code and recommended by roofing manufacturers roofing felt has been eliminated in many previously built experimental homes without noticeshyable effects In addition many production homes throughout the nation have been built without building paper under the singles
Drywall ($283667)-An average cost savings of almost $75 per unit was realized in gypsum wall board hanging and finishing primarily because of the reduction in nails over conventional practice The OVE framing techniques reduced the number of nails by about 30 percent
Table 5 shows average costs of Approach 80 homes by major cost categories compared to conventionally built Las Vegas homes
The total cost savings of Approach 80 over conventional construction techniques amounted to $549186 per unit Following is an item-by-item analysis of the cost savings by major cost category per unit
Fees and Engineering-Fees and engineering on a per unit basis were not reduced A total of $4270212 was paid in this category $3450210 of which was for building permits and sewer power and water fees
24
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Table 5 Approach 80 Total Costs by Major Cost Category As-Built v Conventional
Las Vegas Codes and Standard Practices
Average Cost Per Unit
Cost Category As Built Conventional Savings
Fees and engineering $112374 $112374 0 Raw land 408982 470949 $61967 Land development 829861 1120209 290348 Direct construction 2290476 2414060 123584 Indirect construction 194377 209383 15006 Overhead and financing 328991 354522 25531 Sales marketing 448653 481403 32750
Totals $4613714 $5162900middotmiddot $549186 Percent savings 106
Average cost for 38 units was $4613714 Average cost for 33 units was $5162900 Note Had Approach 80 been built to existing Las Vegas standards only 33 units would have
been possible instead of 38 as built
Raw Land ($61967)-Total cost ofthe Approach 80 site was $15541316 or slightly over $31000 per acre Sixteen percent of the total area was not within the subdivision but was required for two major Las Vegas streets Of the remaining 42 acres 26 percent was required for interior streets sidewalks and common areas Therefore of the original 5 acres only about 60 percent was available for dwelling units Furthermore had existing Las Vegas land development standards been followed only about 50 percent of the land would have been available for housing thereby reducing total yield from 38 units to 33 units This change would have increased total cost of raw land by $61967 per dwelling
Land Development ($290348)-Since only 33 units were possible avershyage land development cost reduction was 290348 or 259 percent
Direct Construction ($123584)-Total direct construction costs would vary with the number of units built but average direct costs would remain the same assuming the housing mix was constant Therefore direct construction cost savings per unit remains the same regardless of the number of houses built
Indirect Construction ($1 5006)-Some elements of indirect construction cost do not vary on a per unit basis while others vary according to total costs and others vary according to the number of units built For example the Approach 80 builder budgeted $500 per unit for supervision which would remain the same whether 33 or 38 units were built General labor security vandalism and contingencies however are budgeted as a percentage of direct costs and therefore will increase as direct construction costs increase
Overhead financing ($25531)-As with indirect construction some items of general overhead are fixed while others are variable according to the number of units Financing is of course variable according to total cost of the project and the amount of time the project takes to complete and sell
Sales and Marketing ($32750)-Marketing costs such as signs and adshyvertising increase on a unit basis if fewer units are built while sales commisshysions increase as the total sales price increases
25
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Deviations Requested But Not Approved
Table 6 shows an item-by-item breakdown of all average Approach 80 costs by major cost category and by cost item within each category Each cost item represented is also presented as a percentage of total cost For example land development accounted for 18 percent of total cost When combined with the cost of raw land each lot represents 269 percent of the total house cost
Table 7 shows the category-by-category and item-by-item estimated avershyage costs of the conventionally built Las Vegas comparison home Percentshyages for each cost item are presented The average cost of developed lots would have been 308 percent of the total
The City of Las Vegas approved many deviations from existing codes and standards Others however were not approved Still others were upgraded from the original request but were below existing requirements
As shown in table 1 lot sizes street rights-of-way street paving widths and dead-end-street requirements were not approved as requested but were approved at less than typical Las Vegas standards Waiver requests on fire-wall construction and concrete slab-on-grade thicknesses were denied
If all requested deviations had been approved substantial additional cost savings would have occurred In addition other potential deviations were not requested because of the certainty of denial For example reduction in electrishycal code requirements was considered but since extreme problems with waiver approvals were anticipated waivers were not requested Also
Table 6 Approach 80 Total Cost Breakdown for Average Unit by Cost Category and by Cost Item
Within Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
Fees and Engineering Architectural plans $17007 04 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 17
Subtotal $112374 24
Raw Land $408982 89
Land Development Trenching 71964 16 Utilities 162322 35 Street paving 209151 45 Sidewalks 57552 12 Curbs and gutters 45192 10 Regrading 19766 04 FenCing 47309 11 Street lighting 30789 07 Barricades 3158 01 Landscaping sprinklers 110789 24 Civil engineering 71869 15
Subtotal $829861 180
26
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Direct Construction Foundations slabs 232388 50 Rough framing materials and labor incl plywood and siding 588814 127 Rough plumbing 124127 27 Finish plumbing 250047 54 Heatingair conditioning 174265 39 Sheet metal 11803 02 Rough electrical 121927 26 Electrical fixtures 7278 01 Roofing 64223 14 Insulation 47202 10 Drywall 155156 34 Windows and doors 96819 21 Finish lumber 7500 02 Finish carpentry 23912 05 Cabinets and countertops 65713 14 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 01 Garage doors 10645 02 Painting 89550 20 Finish flooring 73110 16 Driveways patios walks 88831 19 Clean-up 18300 04
Subtotal $2290476 496
Indirect General labor 33656 07 Supervision 50000 11 Security and vandalism 6688 01 Contingency 104044 23
Subtotal $194377 42
Overhead financing General overhead 59210 13 Construction interest 269781 58
Subtotal $328991 71
Sales marketing $448653 97
Total $4613714 1000
reduced-size plumbing vents have proven effective in many studies but waivshyers were not requested because of a negative response from code officials
The following item-by-item analysis shows the estimated cost savings that would have occurred if all waiver requests had been approved by the City of Las Vegas
Lot Size-Existing standards call for minimum single family lots of 60 x 120 feet Reduction to 40 x 80 feet and 45 x 75 feet was requested with 40 x 90 feet and 45 x 80 feet approved Had the requested lot sizes been approved between 225 and 400 square feet per lot would have been available for either building more units or providing more common open area Almost 12000 square feet would have been available Inasmuch as each lot would contain between 3200 and 3375 square feet three more building lots might have been available had the requested sizes been approved Therefore 41 units
27
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Table 7 Conventional Total Cost Breakdown for Average Unit by Cost Category and By Cost Item
Withi n Each Category
Average Cost Percent of Cost CategoryItem Per Unit Total
---shy
Fees and Engineering Architectural plans $17007 03 Building permits 13808 03 Temporary waterpower 4572 01 Sewer feespower and water 76987 15
Subtotal $112374 22
Raw Land $470949 91
Land Development Trenching 82868 16 Utilities 210908 41 Street paving 305632 59 Sidewalks 90859 18 Curbs and gutters 69546 13 Regrading 22760 04 Fencing 72454 14 Street lighting 51212 10 Barricades 3636 01 Landscaping sprinklers 127576 25 Civil engineering 82758 16 ----shy
Subtotal $1120209 217
Direct Construction Foundations slabs 246012 48 Rough framing materials and labor inc plywood and siding 685285 133 Rough plumbing 125398 24 Finish plumbing 250047 48 Heatingair conditioning 175658 34 Sheet metal 11803 02 Rough electrical 121927 24 Electrical fixtures 7278 01 Roofing 67586 13 Insulation 47202 09 Drywall 162618 32 Windows and doors 96819 19 Finish lumber 7500 01 Finish carpentry 23912 05 Cabinets and countertops 65713 13 Rangeovenhood 23400 05 Finish hardware 13061 03 Glazing mirrors 2405 Garage doors 10645 02 Painting 89550 17 Finish flooring 73110 14 Driveways patios walks 88831 17 Clean-up 18300 04
Subtotal $2214060 468
26
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Indirect General labor 37150 07 Supervision 50000 10 Security and vandalism 7379 01 Contingency 114854 22
Subtotal $209395 40
Overhead financing General overhead 63805 12 Construction interest 290717 57
Subtotal $354522 69
Sales marketing $481403 93
Total $5162900 1000
could have been built instead of 38 and this change would have reduced land development costs from $829861 per unit to $769139 per unit and raw land costs from $408982 per unit to $379056 per unit Total additional cost reduction would have been $90648 per unit
Right-ot-Way and Street Paving-Standard Las Vegas residential street right-of-way is 60 feet and street paving width is 41 feet Deviations requested included street widths of 16 feet for a side street 20 feet for interior streets and a 24 feet wide entry street The approved compromise deviation included a 16-foot side street 28-foot interior street and 36-foot entry street Had the requested widths been approved an additional 6856 square feet of paving would have been saved The 6856 square feet would have created enough land for two more units which could have reduced total land development and raw land costs another $53403 per unit At $540 per square yard for paving costs total paving savings would have been $9567 per unit
Dead End Streets-Las Vegas standards require a cul-de-sac at the end of dead end streets Simple street width dead ends with tee-section turn-around easements were requested This was basically approved except for a break away barrier at the end of one of the dead end streets for emergency vehicle access The required barricade cost $1200 or $3158 per unit
Off-Site Requirements-Approach 80 was required to pay $14363216 in off-site improvements This amounted to almost 46 percent of all land development costs (see table 2) Since no deviations from Las Vegas stanshydards were allowed no cost reduction was experienced
Off-site costs included paving one-half of two Las Vegas streets Pavement widths of the two streets were 88 and 68 feet One street Smoke Ranch Road was originally designed as an arterial street that would eventually connect with a freeway about 2 miles west of Approach 80 However this intersection supposedly had been changed and Smoke Ranch Road was no longer to be a major arterial street
If Smoke Ranch Road and the other street Torrey Pines Drive were deSigshynated as collector and subcollector streets respectively 36-feet-wide paveshyment would have been adequate according to NAHSs Residential Street Development Standards If so paving cost reduction would have been $36450 or $959 per unit
The concrete block wall arou nd Approach 80 cost $1797742 The practice of enclosing a subdivision behind a high wall is debatable and many comshymunities especially in the West have such requirements If it had not been required a $47309 per unit could have been saved
Street lighting along Smoke Ranch Road appeared to be excessive Five 250 watt HPS Luminaire street lights were installed at a cost of $1300 each If
29
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Smoke Ranch Road were downgraded to a collector street three street lights would have been sufficient a savings of $2600 or $6842 per unit Street lights by the way were installed directly in the middle of the 6-feet-wide sidewalk
Off-site sewer water and utility costs amounted to $2207230 including trenching These costs included about 1 300 feet of off-site sewer line to connect to the nearest available existing line Approximately $7800 would have been saved had the sewer line been located as near Approach 80 as the water line This amounts to about $205 per unit
Fire Wan Construction-Early meetings with building code officials indishycated that the requirements for a 30-inch high 2-hour fire rated parapet wall atop roofs located on property lines would be waived However once construcshytion was underway city officials decided the parapet walls were required
Besides being quite unsightly the add-on parapet walls were expensive Average cost was $65200 per unit Two units were exempt from this requireshyment because these units could each be 3 feet away from property lines (The units were still 10 feet apart) The split level home and fourplex units were also exempt because they did not contain 1000 square feet on anyone level and had no attached garages Therefore average per unit cost of the parapet wall for all 38 units was $37763
Reduced Slab Thickness-A request to reduce slab-on-grade thickness from 3V2 inches to 2V2 inches was denied although the city did allow 2V2-inch slabs in three experimental units with the condition that the builder sign a letter of responsibility for the performance of the slabs The request was based on the condition of the subdivision soil and load-bearing tests which indicated that a 2V2-inch-thick slab would be adequate for normal residential loading conditions Had the 2V2-inch slab been allowed in all 34 slab-on-grade homes savings would have amounted to $17500 per unit
Table 8 shows the potential additional cost savings that might have been realized had all items requested for Approach 80 been approved and had off-site requirements been relaxed
Table 8 shows that an additional $382644 per unit could have been saved if all requested waivers had been approved and if off-site requirements had been relaxed This change would have raised total cost savings from $541986 per unit to $931830 or a total savings of 18 percent
Table 8 Approach 80 Estimated Potential Cost Reduction ot Items Not Approved by the City ot Las Vegas
Cost Item Per Unit
Lot size larger than requested $ 90648 Interior streets wider than requested 62970 Dead end street barricade required 3158 Off-site requirements
Street paving widths too great 95900 Fencing not necessary 47309 Street lighting too intensive 6842 Sewer connection too remote 20500
Parapet fire walls atop roofs 37763 3Y2 I thick slabs required vs 2Y2 I requested 17500
Total $382644
30
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
Conclusion
The Common Area
The Approach 80 project was an unqualified success in what it was attempting to accomplish It proved that comfortable safe and attractive homes can be built at substantially less cost if government officials land planners and builders come together with a common goal
Approach 80 was not however a cure-all for affordable housing Indeed the average sales price of about $51000 was about $10000 lower than comparable homes in Las Vegas but the price and high interest rates still make owning a new home impossible for too many Americans
The homebuilding industry must continue to search for solutions to the massive problem of building affordable dwellings These solutions may be found by continually looking at new products materials and methods that will lower costs and increase value But more importantly builders and land developers must work closely with those governmental agencies that are involved in regulating the housing industry to eliminate excessive regulatory costs and to streamline the process of providing shelter for the majority of Americans
31
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005
US Department of Housing and Urban Development Office of Policy Development and Research 451 7th Street SW Washington DC 20410
National Association of Home Builders 15th and M Streets NW Washington DC 20005